For speed, reliability, durability, you want an SSD. Take a look at Intel's offerings, you've got top performers at a reasonable price at 40GB and 80GB with them, more if you wanted - eg this thread
http://forums.hexus.net/current-barg...0gb-165-a.html
As for 10k RPM hard drives, a 36GB or 74GB Raptor is a massive waste of money - they're fairly easily outperformed by standard 7200rpm drives these days. You'd want to be looking at a 150GB or 300GB Velociraptor instead, but even then I wouldn't bother - the speed improvement over standard hard drives just isn't big enough in my eyes to warrant the additional cost.