Run the sfc /scannow command...or repair install XP, that's what I would do.
I don't have a Dell and don't know if this is one of your options.
How to Perform a Windows XP Repair Install (Stevens) - http://www.michaelstevenstech.com/XPrepairinstall.htm
FWIW: dwwin.exe is Dr. Watson, a reporting tool built into XP that is activated by some problems.
You can try running chkdsk /r command from Task Manager and see if that helps. File/New Task(Run)...type chkdsk /r (space between k and /) and hit Enter. Type Y in onscreen box, hit Enter. Reboot the system.