Should I Play BG1 before BG2?

ull get more out of it if u play BG1 first. BG1 is also a top class game so id definately recommend it.

however its not necessary to play BG1 first. a few things might be a little confusing initally but ull be brought up to speed pretty quickly.

ideally get BG1 first, but its not needed.

Here's what you do: you get both games with expansions for both (I am sure there is a cheap bundle somewhere) and you download a program called easytutufollow the instructions there and it will change baldur's gate 1's engine into the BG 2 engine and as a result you can have all the characters and options in BG 2 in BG 1 and you can play both games and expansions like one huge game. I am currently playing through it that way with a sorcerer. I admit I beat BG 2 first but I am now replaying the games this way so I know what when on before. In BG 2 the game helps a little bit to tell you what's up but I think it is better this way. It's a heck of a lot of hours of gameplay lemme tell you.

You don't have to, BGII + TOB expansion stands on it's own pretty well. It'll be a mild benefit if you know the storyline, and the very start of the game may be a bit confusing if you haven't played it but it's more then capable of being played individually.

The biggest downside would probably be missing out on all the NPC's references and "in jokes" about the previous game, it's nothing essential and the base storyline is almost entirely unaffected by any lack of knowledge of the original.

If at all possible I would recommend playing the BG I first though, it's an absolutely stellar game but if you go back to it after playing BGII you'll miss out on a lot of the enjoyment because there is always the overaching experience of how dramatically superior BG II turned out to be, which tends to pale the experience somewhat.

With a game with such a strong storyline, and so many throughly enoyable NPC's with what is still probably an unparalleled amount of depth to them you'll miss out on the emotional attacgment to what happens to Imoen in BG II, and she'll probably come across as a fringe character. The Jaheira/Khalid revelation early in BG II will seem meaningless to you as well.

All said- the base story line stands on it's own easily. But there is so much else, that I strongly recommend playing BG I first.

Stellar games, and easily far far superior to anything that's come out in the last half decade or so for RPG's.

If you eniy BG I/II look for the IceWind Dale series... same engine, same gametype but without quite depth BG offered. Great games nonetheless.
Planescape Torment is a somewhat similar gametype as well, and one of the incredibly rare games that can stand up to BG II in quality if you can manage to hunt down an old copy.

If you play BG2 first, you probably won't enjoy BG1 as much (you'll know the plot-twists, you'll dislike the low-level battles, etc.).

If you've got the chance, play them in order. You might also want to consider playing the whole way through the series with a single character.