Hi Reflexa and welcome to this BBS
For my opinion scsi is not needed. You can manage with two IDE 7200 rpm Harddrives. One for a systemdisk and the other one dedicated just for audio.
When going the PC -rout for me there would be two ways to go with the software: Cakewalk or Cubase. Some guys would also advise you to go with N-tracks or Cool edit pro but I'm not familiar with those software.
One last tip: USE the search engine of this BBS. It is one of the most powerfull tools in the world that will help you to get in to this recording schait...
You're not alone out here.
Riku