Spyware and such

Even though you got rid of that one file, I would take a look at this program: Spybot - Search & Destroy

It is updated often (And you can download the updates strait from the program) - But I use this program often to to searches on my PC.

Not only does it find spyware, and "highjacking" programs - it also searches for "bad" cookies, or cookies from sites which may use that information for "bad" things. It will also clean and remove files. So it is a good thing to download and use every once and awhile. (Only down side is it is not the most user friendly program, but it should not be too hard.)