of corse you wanna go with a pc avoid macs like the a sickness (just kiding sorta)
best advice i can give you is unless you wanna built it your self go to best buy or curcuit city and look at the media center pcs and find one thats in your price range
as for what i recomend
try go go with an amd 64 bit prossessor if not atleast an amd
no less than 512mb ram recomended a gig
as for a video card go with something like a ati 9600 or better
that il get a machine that will last you
