Wow, ok, the problem has subsided for at least a little bit. My wife seems to think it may be something she accidentally downloaded while surfing MySpace.
The text cursor acts as if the left arrow key is being held down, causing me to type everything in reverse. This is true in Windows Explorer as well.
Aside from that, the computer has been running quite a bit slower lately than usual (it's about 4 years old). I've also been having trouble with the mouse a bit, though that may be just because it is wireless.
On a separate occasion, the text cursor did the opposite; it acted as if the right arrow key was being held down. I consider myself moderately technically capable, but this one is just beyond me. Any help would be greatly appreciated. Thanks!