Well... any pc with:
- AMD/Intel 800mhz cpu
- 256MB RAM
- DX7 3D GFX card wth tv out recomended
I think this covers the basics. If you want to watch HDTV just double the cpu power, ram, etc. Better yet visit technisat's site.
Skystar2 don't like nforce4 chipsets.
As for programs i'd say, go for ProgDVB or MyTheatre plus a softcam emu like S2emu and a working key file, plus a new transponder and channel list. Not much can go wrong with these choices.