I know several people are playing Resident Evil 4 for the holiday, and I thought I'd offer the sketchy draft I started of a miser's guide to RE4.  I went through the game once trying to figure out the optimal way to handle each part... if I missed (wasted ammo), or took damage I'd restart from the last checkpoint until I got it right.

I was going to set it all down and put it on GameFaqs so that I could claim I was a "freelance journalist" at parties, but as a lot of bright ideas I have, it somehow managed not to happen very much.  I say "very much" because I did record the best route I found through a couple of areas later in the game that were where I happened to be playing through at the time I thought of writing a guide and before I got distracted by something shiny.  I also jotted down some general strategies, and since I doubt I'll ever really sit down and finish the guide, I'm sure as heck going to recycle those here!

Watch out... as spoiler-free as possible, but describes most of the basic enemies you'll face in the game.  No bosses, though.

General strategies:

Knifing is Free
For unarmed villiagers/monks in most situations, your knife should be sufficient.  Aim for the head and each hit should stagger them a little, and you can actually keep several enemies at bay at once like this.  Be careful of the rabid lunge they sometimes do, though, because they seem to be impervious to any kind of knockback from knife damage during this.  If they go into the full stagger animation, kick them down.  When they fall, from a kick or repeated knifestrokes, knife them like crazy, again aiming for the head if possible.  For the helmeted enemies, aim for the legs to make them fall, then go at the torso/legs.  Suplex when possible.

One Shot (and a lot of stabbing), One Drop
Enemies with weapons or in groups CAN be handled with the knife in some cases, but I indulge myself with 1 handgun round each.  Shoot the enemy (or lead enemy) in the head, then kick them down.  If they're advancing with their hands blocking their faces, shoot their kneecap out to drop them.  Once on the ground, knife them like crazy.  Shoot helmeted enemies in the knee, then suplex if possible and knife them on the ground.  If someone lobs a Scythe at you, one handgun round will knock it out of the air, leaving them unarmed.  In groups, shooting one enemy in the head to enable a kick can take down multiple opponents, and if they land near enough together, you can knife them all at once.  Budget one bullet for each enemy, then try to come in under par.

Ladders Are Your Friends
I don't know if it's the parasites infesting them, or if there's some inbreeding going on in that village (everybody does look an awful lot alike), but the enemies aren't very bright.  If you can get to the top of a ladder, they'll line up to climb up after you.  Stand at the top and swing your knife at them.  One hit will knock them down, and they'll take extra damage from the fall.  They'll keep climbing right back up for more, though, until they're all dead.  Just make sure that your position at the top of the ladder is secure.  You can also, of course, kick the ladders over on them, but then you have to wait for them to raise them back up again.  I just knife 'em.

I Don't Want Any *&^#$ Encyclopedias!
If you run though a normal door (not a reset point) and let it close after you, pursuing enemies will cluster outside it and try to hammer it open.  As soon as the door begins to shake, kick it open and you'll damage anybody standing right in front of it.  By the time they recover, the door has usually swung shut again, and you can keep repeating the process.  Be ready with a weapon (I recommend the shotgun, as there's usually a crowd out there) because if the crowd is large enough, the ones in the back won't get knocked over, and may make through the door.  You can either let them in and deal with them with the knife or blow them back and let the door close again.  If you're into pyrotechnics, you can also kick the door open and lob a grenade out (be careful not to get caught in the blast) to deal with a large crowd.

Fire Good!
Use the environment and even other enemies to your advantage.  Explosive barrels are often placed where they'll do you a lot of good, as are the oil lamps you can shoot to drop on enemies.  One handgun round to a stick of dynamite that an enemy is about to throw or has just thrown at you will detonate it, killing any enemies in the blast radius.  Try to make enemies throw explosives at other enemies before taking them out, and trick enemies into walking into tripwires or under catapult shots whenever possible.

Unarmed Ganados/Zealots
Knife 'em.  If you want to make it extra easy on yourself, give them a handgun round to the face first, then kick them down.  If you keep at them with the knife, they shouldn't be able to recover enough to attack again.  Be careful of their rush attack, though--if they start hissing, back up or plug them in the head with the handgun.  During their charge, they shrug off knife damage, but they don't run that far, and are vulnerable for a second after missing.

Pitchfork/knife Ganados
They're vulnerable after missing a swing, but it's generally easier to just give them a headshot and follow up with the knife.

Hatchet Ganados
These guys can store a lot of hatchets in their back pockets!  They never run out, in fact, so take these guys out quickly.  They have a pretty fast melee attack in addition to their range attack, so it's definitely worth setting them up with a headshot.  You find them skulking at the back of crowds a lot of times, lobbing hatchets while their friends keep you from getting at them.  Leon can knock hatchets, scythes, and even crossbow bolts out of the air so use a bullet if you need to--better that than having to use a healing item!

Torch Ganados
These guys are really easy.  If they try their overhand swing, which they wind up for really slowly, just walk backwards.  They'll miss you by a mile, and then be vulnerable to you dashing in an knifing them.  If they take a deep breath and prepare to blow fire at you, just hit them once and they'll set themselves on fire.  You'll never even need to use a gun on these guys.

Dynamite Ganados
Try to get these guys to take out some of their buddies, then wait for them to light a stick and shoot it in their hand.  It will explode and kill them and any other enemies that are nearby.

Flail Zealots
Contrary to what some other guides say, these guys are not carrying Maces.  A mace doesn't have a chain.  Anyway, their attack is pretty fast and has good range, so use the headshot/kick/knife method.  If they get back up still holding their flail, you may have to use a second bullet, but keep on them with the knife until the very last second, and they might go down before you need to.

Shield Zealots
One good shotgun blast should take out their shields, after which they become Flail Zealots.  Try to get as many shields as possible in one blast.

Scythe Zealots
Don't mess around with these guys.  They do vicious damage with range or melee attacks, and their scythes somehow home in on you when thrown.  That's fine, though--you actually want them to throw their scythes.  Once thrown, you can knock them out of the air or duck behind cover and deal with them like unarmed opponents.  They don't pull more scythes out of their back pockets like the Hatchet Ganados, and they won't pick them back up even if they walk right over them, so get them to throw away their weapons and they're a lot more manageable.

Crossbow Zealots 
These guys are wussies.  They may be really annoying at a distance, but if you get right up in their face, they'll try to run away.  Take cover until they've shot their two arrows, then run out and knife them while they reload.  They don't use melee attacks no matter how open you leave yourself.  If you can't get close, snipe them--it's worth the rifle round to get them off your back while you're fighting a horde of other enemies.  They aren't very tough, so you shouldn't even need to hit them in the head with your rifle--anywhere will do.

Helmet Zealots
You can't knife these guys in the head, so go for the hamstrings.  Keep at their legs, and they'll go down.  If they're armed, shoot their knees to drop them, then knife their torso.  Suplexing doesn't do much to them, and takes you some time to recover from, giving them time to get up.  Just keep at them with the knife instead.

Headbursters
If a parasite bursts out of any of these enemies, take it out quickly.  If you shoot it right away, one shotgun blast or even a handgun round can take it out before it become a real pain.

Novistadors
The first type you run into will be initially invisible and move very fast.  Scout ahead with your rifle zoom and snipe them when possible.  One headshot with the rifle should take them out.  The winged variety is easier--try to knock them out of the air for an instant kill.  For both types on the ground, the shotgun is your best bet.  If they get too close, you get an option to kick them back, but it goes by quickly.  The kick animation swings the camera around for a few seconds, too, which can throw you off.  Better to make sure your back is always clear and use the shotgun to blow them back when they get close.

Colmillos
I really hate these things.  The pistol won't get you very far with them, and you can't outrun them to find cover.  The best you can do is get your back to a wall, wait for them to lunge, and blast 'em with the shotgun.  Luckily they don't show up very often.