New Computer - Old Games?

[Natasha]

Hi there. I am on the brink of buying a new computer. Very exciting, after
years of limping along on a beast so broken that I have not been able to
play the kinds of games I love (Including all the Morrowind/IWD games).

So, the question is.... How do I maximize being able to play the games I
want to play (existing) without making myself immediately obsolete?

Anything I should consider in terms of OS, hardware, video cards, etc? Will
these games work with duo or quad processors? NVidia 8800 GT cards? SLI?
Etc? Anyone playing on Vista? 32 bit vs 64?

Sorry if this is off-topic, but.... I really want to take these issues into
consideration and you guys are playing the games I want to play.

Thanks in advance!