I don't have the money to buy a VelociRaptor or a SSD. Someone said that I could have a RAID setup that would be faster then having just one HDD. Two 500GB drives in a RAID? Can someone help me understand this better?
Either a velociraptor or SSD would smash RAID in that regard. RAID is for MB/s, velociraptors and SSDs are for response times. Unless you have a large file server, you will not need RAID for speed - its main use is for redundancy, i.e. if a drive goes, you still have the data there. For the low budget system builder, a single 32MB cache drive like a Caviar Black is ample.