Trojan dc.exe, fun.exe, other.exe, win.exe, winsit.exe

Firstly use msconfig to remove the trojan startup programs. read the below blog.
Then use process explorer to delete the self replicating trojans.

http://freewareindia.blogspot.com/2008/07/msconfigexe-windows-xp.html
http://freewareindia.blogspot.com/2008/07/trojan-ntosexedcexe.html