Did you try Start > Run > and type dfrg.msc in the Open line. Click OK
Start > Administrative Tools >Computer Management. Expand Storage and select Disk Defragmenter
Kelly's corner has a tweak scroll down to Line 280 on the left side to 'Restore Defrag.exe'.
Run a disk cleanup and chkdsk bfore the defrag.
Personally i'd suggest you download this tool, try it its free, the paid version has some neat features.