My HD is 40 Gb.

All my docs and programs are only 4 Gb.

'Dell', in 'Documents and Settings' is too big: 24 Gb. 

Yet, I can't see what all this space is used for. It contains 'Cookies', 'Userdata', etc... that are all only a few Kb, and it also contains another 'Windows', which is empty. Where are these 24 Gb ?

The system refuses to delete 'Dell'.

How can I reduce the space taken by 'Dell' ?
Help ! Thanks a lot.