Some applications, even after being uninstalled leave behind crap that will slow you down. I don't entirely know how to describe it, since I'm not sure what's going on behind the scenes, but here's what I do:

1. Reboot the machine and log on as administrator (NOT your own account).
2. Rename your old profile -- "C:\Documents and Setting\username" -- to something like "C:\Documents and Settings\username.OLD" (you can't do this if you're logged on as "username" or if you haven't rebooted since you were).
3. Log off admin and log on as yourself. Windows will automatically create a fresh profile for you.
4. Open up applications (Firefox/MS Outlook/etc...) and see how it fares.
5. If it's looking good, go ahead and retrieve stuff from your old profile like your desktop folder and My Documents, or .pst files or anything you might think is important in "C:\Documents and Settings\username\Local Settings" and "C:\Documents and Settings\username\Application Data" -- usually things used by Firefox and Outlook, etc. For the most part applications will rebuild from scratch.

If that doesn't do it, you could try some sort of registry cleaner, but if you're at that point I'd rather just reinstall Windows. Alternatively swap out for a hard drive from another computer. And if THAT doesn't work, then you know it's a hardware issue.

Are computer science and philosophy related? Yes! I have BA in philosophy, and I focused on cognitive science and artificial intelligence, where the two meet head to head. Computer science needs philosophy in order to help evaluate the status of machines in terms of whether or not they have consciousness. And philosophy needs computer science to help answer open questions in the philosophy of mind.

Also, the two have a mutual interest in the study of information--what is it, how do you use it efficiently, how do you organize it, how do you process it, etc. If you have any interest in it, you should definitely check out Luciano Floridi--he's part of/started a movement he calls The Philosophy of Information that encompasses but AI and the philosophy of computing in general, including questions in ethics.

Currently I'm taking courses in computer science (and I work in IT), and I hope to start grad school in cognitive science next year. So yes, for me philosophy and computer science are intimately entwined.