Today at a Microsoft thingy I won a full copy of Windows XP professional.

I would like to put it on my Dell XPS R450 at home which currently has Win98 and 64mb ram.

Questions:

I need to add memory - what's the skootch on ECC vs non-ECC?

Will all the 3-D accelerated games work on XP or will I have to toss them?

Where's the best place to buy additional memory?

Should I keep my 64mb and add on, or just get a bunch of 128s (which I think are the biggest for the XPS R450) and toss the 64mb?