Windows Defragmenter not working….

Alright, seriously wierd problem. My windows defragmenting utility doesnt work….it starts up and everything but when i hit either anilyze or defragment….it doesnt do anything no matter how many times i hit it! The only thing ive done recently is do a registry cleanup with some utlity called JV powertools, and install windows vista RC1 on another partition. Other than that i have no idea whats going! Please help, anything would be greatly appreciated!

(I have done a virus scan with avast!, and have done spy-ware searches with windows defender, spybot, and ad-aware pro and found nothing)