A week ago, my hard drive started making an odd clicking noise, and, after a call to Dell support, it was clear the damn thing was going to die on me, fast. Dell sent me a new drive, free under my warranty, lickety-split, and last night my job was to move everything over to the new hard drive.
Since I run Windows Vista Ultimate, I can use the very nice Complete PC Backup feature to move my files over to the new hard drive, and I did. Overall, it worked out nicely. You can also use this feature if you bought a new bigger hard drive and want to move everything over to it.