This is one of the common problem which most of us face. Some Softwares still have the entry in Add or Remove section of windows XP even if we have UnInstall the application or program.

Here is the Trick on how to remove them from Add / Remove Section

1)Go to Run & than type regedit.
2) Now Navigate to the String HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\uninstall.
3) If the software name is still here which you removed already, delete it from here.
4) This will delete its entry from the windows ADD/ Remove Section
This should work on Windows Vista as well though I have not tested it yet. I will update here If I do.

TIP: Always use Add/Remove utility of Windows XP.Vista to remove program.

That's It...

Cheers!!!