Can Anyone recommend a good free Defrag Program

[DomSQ]

Hey everyone,how's it going?,I recently tried to do a Disk Defragmentation by using the default microsoft one that is built in with Windows Vista,though after waiting 7 hrs for it to complete,it still was saying "Defragmenting Harddrive,this may take from a few minutes to a few hours"

So I finally cancelled the defrag as I don't want to leave my computer on for anymore than 8 hrs,I'm guessing that an Error Checking will fix that problem of the defrag maybe not working,but I was wondering can anyone recommend me a real good,safe to use Free Disk Defragmentor that's better than the standard vista one?as I'm saving up to buy O&O sooon.

Thanks everyone