For the first time in the 3 or so year i've had this computer, I decided to do a defrag. my question is: how long is the defragmentation supposed to take? i was defraging my C: drive and after 20 minutes it was only 5% finished. is this normal?
Depends on the speed of your system and the level of defragmentation on the drive. I presume it is heavily defragmented and there is a lot of data to reorganize. i would get a hold of Diskeeper 9.0 Pro!! It will speed up your HD!!!
After 3 years of usage it's normal for a defrag to take very long.
Don't use Windows Defrag. Programs like O&O Defrag, Diskeeper and PerfectDisk are much better.