I think both drives are 5400 spin, not 100% sure. There are IDE though. Coming down to customizing Windows at this level (partitioning C:...) seems to be polishing a turd...
I haven't migrated my system over to 2000, mostly just out of straight fear of the foreboding "driver issue", but I think most of the gear I've got is compliant now...
Speaking of 2000, though, is it capable of utilizing more than 256MB of RAM? I heard two ugly rumors, (one from Gateway.com) that 1) Windows 95 can't page more than 64MB of physical memory, and 2) Windows 98 can't page more than 256MB. Have you heard this?