I hate IE. Too many problems always.
I had a similar problem to you while using firefox years ago. No one could figure out my problem. It got progressively worse and worse, and only occurred on one forum. No one else on the forum experienced anything like it. (And no, the forum was not playing tricks on me or placing me in miserable users group or anything. I know because I was a senior mod. for years there.
) I have never had any other problems with firefox, except that time.
After that time, I switched to Opera. I was forced to switch at first because no one could figure out why my firefox was acting up on that forum. To this day, I like Opera and use Opera..... except for right now because I am on a borrowed computer.
You can get Opera here if you want:
http://www.opera.com/