I used diskeeper for defragmenting my C drive on vista. Initially I had 2.6 GB free space, after defragmentation, it is just 480 MB. What happened? Please help to recover the space. Defragmentation is not supposed to decrease the storage space!!!
Edit 1:

Obtained by Scanner tool as suggested by ~harrymc in his answer

Edit 2:
I do not have much idea of above diagram. But I can infer one thing. From the above diagram, it looks like there is a problem. For e.g., in the green portion(representing folder) on the right at first level, there is a small portion on top right hand side which does not lead to any actual file. So the portion below it must not have been green. It should be free. Am I correct in my interpretation ?
Edit 3:
I ran chkdsk /f. It ran at restart. It removed some index entries. It gave message like this:
removed $0 of file 25
repeated many times. But the problem is still there. Please help.
Edit 4:
Mysteriuosly, just 2 minutes ago it has started showing me free space as 2.3 GB. I swear, I did not delete any thing Just 4 minutes ago, it was showing me 290 MB. I dont understand, how suddenly that space got freed. What is happening? Could anyone explain? I got this after running scanner now.
