Well, there are a lot of places the startup information for an application can be.

First, I'd look for it in the registry.

Click start, then click "run". Type in "regedit". It's short for registry edit. Click Hkeylocalmachine, then software, then Microsoft, then Windows, then currentversion, then Run. (I had to check the exact location.. I had to delete a few entries there as well. Thanks for reminding me.) There will likely be a few entries in there. If the culprit you want to delete is in there, delete it. It should work.

Then you can check the startup folder. It's in the startmenu button under "All Programs". Remember, this is all assuming you're running XP.

If this doesn't work, check out Microsoft.com. You should find some help there.