Doesn't matter too much...
I dunno how fast your particular drives are, but I'd maybe go for SCSI system (eg /, boot, swap) and IDE for /home /usr and /var... It really depends on where most of your files are going to live, because you'll fill that 3GB pretty fast. If you keep loads of junk/code/mp3/divx in /home you could even dedicate that whole ide disk to /home... it's your call really. Performance wise it probably won't matter a whole lot.
<i>Do I look like I care?</i>