Works with Windows2K/XP/Vista/7.  Freeware.

The commands are simple:

kill:processname (this command takes wildcards)
kill:calc.exe will terminate calc.exe

findfile:c:\,findme.exe
This command builds a list of all files matching
"findme.exe" and saves them in memory.

delete:findme.exe
This command deletes the specified file
If this is preceded by findfile it will delete all found instances of the file.
Files in use or otherwise locked will be removed on reboot.

deletefolder:c:\test
This command will delete an entire folder and all subfolders/files

rename:c:\windows\system32\calc.exe,c:\windows\system32\calc2.exe
This command renames the specified file
You need the full path of the files for this

regremove:hkcu\Software\MooSoft Development,test
This command removes the specified value from the specified key

regadd:hkcu\Software\MooSoft Development,test=test
This command adds the registry value specified.

Sample script to remove malware from the WinLogon shell:

kill:malware.exe
findfile:c:\,malware.exe
delete:malware.exe
regremove:hklm\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon,shell
regadd:hklm\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon,shell=explorer.exe

A script can be loaded from a file or copy and pasted into the Paste Script window.

Download ScriptYClean here.

View a sample script