1. another way to remove windows messenger--click start, all programs, accessories, system tools, disk cleanup, more options tab, windows components, you should then see windows messenger in the list, and if it is installed remove it.
2. download, install, update and run Spybot and Adaware. You can find them both at cnet.com in their download section. Run them both periodically.
3. click start, run, type msconfig, click on startup tab. Uncheck all unneeded entries. If unsure about an entry, go to answersthatwork.com and look it up on their tasklist. Some intrusive apps will return at your next startup and answersthatwork.com will also advise you about how to deal with those.