Agreed - its worth the few extra dollars for a 7200 RPM HD. Will make a noticable difference in boot time also. I also recommend the IBM 75 GXP series.
Or you really go all out and get 2 SCSI 15K RPM drives and put them in RAID 0. That would be sweet - except that you'd spend a lot more.
A more realistic suggestion - instead of geting a 60 or 75 GB drive, get like 2 20 or 30GB drives and a Promise Fasttrack card (or get a MB with a RAID controller) and use RAID 0. Then you will have almost the same speed as one of those 15K SCSI drives.