Ok, i have an 80 gig hard drive for my OS drive and it's too full. Found a good deal on a 250 gig drive so i got that and a cheap external enclosure. My idea (and something i've done with non OS drive swaps) was to just copy everything to the external drive, crack it back open and switch it with the drive in the computer. I get a bigger internal drive, and a spare external in the process. Well, thing is i activated the compression on the vista OS drive, and when that happened it split the disk into two partitions, one is very small and has about 500 megs taken (but completely inaccessible) by files that couldn't be compressed. I don't think a simple drag & drop will work for moving the OS drive. I really REALLY don't want to have to reinstall windows, and since the only change is the HDD i shouldn't have to. Could anybody offer any suggestions?