I'd go for nvidia graphics card, disks, DVDRWs are afaik all good in compatibility terms.
If you'll go for Intel Core 2 (which has currently best price-performance ratio, I think), I'd pay a lot of attention of what sata controllers are onboard (probably also other MB components - network card, sound card, chipset...). I set up an core 2 box with an Asus MB recently, and I must tell that I was not impressed with the compatibility of JMicron sata controller and also the "onboard" (both are defacto onboard, but one is more integrated...) one did not work without some tweaking. 2.6.19 kernels seem to adress this sata mess (I used 2.6.19.x on the system I installed), but this kernel is not available on slackware install disk, so you still have trouble installing. But there is a lot of helping material on LQ and other forums...
However, if you choose AMD, nforce-based MBs tend to be very smoothy detected, afaik.
So, I think the only component you should _really_ be carefull when choosing, is motherboard.