[anarres]

As others have said (and if you can afford it), you really should consider a proper upgrade to your system, namely the motherboard.

Of course once you think about the costs of that, it's only a little more to buy a new "barebone" (i.e. mimimal basiscs) system. These consist usually of a motherboard, case (usually with PSU - power supply unit) and (again, usually) memory (RAM). You can then move across your harddrive, CD/DVD, floppy, cards, etc.

The benifit of a barebone system over a motherboard is that they do the "scary" part - namely putting the MB in the case. Actually this is an easy task if you've done it just once before, but you must take precautions like avoiding static build up and not touching chips on it and not letting the MB have direct contact with the case, even around the screw mountings. If you feel you can tackle this task them by all means buy a MB and we can give you advice on it here.

The other main issue around MB's is to make sure it fit's your case (obviously not an issue if you buy a barebone system). Once installed there may be further issues such as possibly reinstalling your OS (been known to be an issue when CPU type changes, for ex Intel to AMD, and also known to be an issue for simple MB differences like different chipsets).

Sorry there is no easy answer - it's a minefield (albeit a lot safer than 10 years ago). If you have the cash, go barebone and move across your cards. If not, then maybe we can help you choose a MB anyway, although I would NOT recommend taking apart your old PC to fit it unless you have a second internet connection you can use to access online (hehe - I've done that a few times and regretted it...).