I use and recommend PerfectDisk.
PerfectDisk Version 8.0, the world’s most popular and thorough disk defragmentation solution, combines speed, thoroughness flexibility, control and ease-of-use to help improve PC and server performance.
What’s new in PerfectDisk build 8.00.66
PerfectDisk Command Center
-Setting License Key Wizard in non-wizard mode (Tab Mode) did not work correctly. This has been fixed.
-We corrected a bug in thread pool on console which could have caused the Console to crash in high activity conditions.
PerfectDisk Client
-When Bitlocker was enabled, boot time defrag passes would abort since bitlocker prevented updating certain files. PerfectDisk has worked around this issue.
-We corrected a bug in memory allocation when performing boot-time defrag passes on X64 processors.
-We changed the boot-time defrag Verify stage to allow the bad cluster file to point to cluster which do not reside on the disk. This can occur if the volume was resized after bad clusters where identified.
-PerfectDisk will no longer display drives which cannot be defragmented. We will only display fixed drives formatted NTFS, FAT, or FAT32.
-We corrected a bug in the file exclusion enumeration. In earlier versions we would have attempted to move files in the System Volume Information folder even though they were excluded. This was do to the fact that these files did not allow the LocalSystem account to open them so the name could be converted to a File ID. This bug has been corrected.
Update from within the program.
or
Download from Major Geeks (30 day trial).
More info at the PerfectDisk home page.