I don't really know much about PCs....

.....And I'd like a bit of advice. Right, my PC is a Dell somethingorother E520. I think it's inspiron, but I may be wrong. Would someone with my computer skill (i.e none) be able to install this;

(http://www.amazon.co.uk/XFX-Nvidia-Express-graphics-card-PV-T86J-ZAFG/dp/B0012EIP2I/ref=pd_sbs_w_h_?ie=UTF8&qid=1201718098&sr=8-1)

graphics card? Would it let me play games with high requirements, and would I have to buy a whole host of other stuff to bring out its potential? Sorry if these are stupid questions and sorry, I don't know how to put the link into a little clickable format.

In general for graphics card installation (not sure exactly how much you mean you don't know about them):

1. make sure you have a free motherboard slot for the card, which you will likely have

2. find out what slot it is - PCI, AGP, most thesedays for games will be PCI-E. Make sure you get a card that is the right slot type!

3. to install it you do need to open the case up (obviously make sure the computer if OFF and unplugged when you do that). You should really ESD-ground yourself (do you have a wrist-strap? or something similar) and also only touch the card at it's sides, and not touch the contacts (the bit that plugs into the board). Also a good idea to ensure there's nothing (like fluff, or way worse - any metal or plastic fragments) in the slots or on the contacts, so install it in very well-lit conditions.

Push out or take out the expansion slot (where the bit on the card with the plugs will go) and to plug the card in just make sure you push it into the slot flush (not one end then the other end - plug it in all at the same time).

4. You'll probably need to install drivers, these should either come with the card (on a CD or a DVD), or they'll be at the manu's website for download. Windows should see that you've added the card when you power on the machine, and will ask you to install the drivers, it uses a wizard to do that and it's pretty straightforward.

One thing on some BIOS - you might need to change the BIOS settings to use the card for your video-input. It'll read something like 'Onboard Video' and you need to change that to 'disabled' instead of 'enabled'. If you weren't using a graphics card beforehand (ie - you have onboard graphics) then the BIOS would be looking for the monitor to be plugged into the motherboard directly, whereas with a graphics card you plug the monitor into the card instead.

Sometimes these update automatically, but it's worth knowing about in case you get a blank screen and think it's broken - it's more likely the BIOS is still trying to see the monitor from the motherboard port.

It sounds complicated but it's not really that hard, lots of people do it. As for if that card's any good - I don't know, I didn't look at it. Type in it's product name / number to google or another search engine and there should be reviews and benchmarks for it.