We were hacked…

We have two new w2k servers (web & sql) that are both running IIS (the web is also running ftp). Some hackers broke in and created directories for storing mp3s, movie’s etc. I am trying to delete these directories, but I get an error: cannot readfrom the source file or disk. How do I delete these directories (these directories main directory is just spaces instead of letters or numbers. I am also getting the following error in event viewer a lot (does this mean anything)?

Event Type: Error
Event Source: NetDDE
Event Category: None
Event ID: 206
Date: 2/21/2002
Time: 4:26:54 AM
User: N/A
Computer:
Description:
Listen failed: 15:

Please help… Thanks!