IE not accepting every keystroke

I'm running IE on MX. I like IE because of it's compatibility with all the other MS programs. But recently it has started not accepting ever keystroke, for example if I'm not watching what I'm typing and retyping every letter that doesn't appear, if I was to type:
"The quick brown fox jumped over the lazy dog" it would come out like this:
Th quick brownfox juped over t lazy og.
I have tried downloading the latest version of IE and reinstalling it. It seemed to make a bit of a difference because it was really bad before I did it, but now it seems to be getting progressively worse again.
Any suggestions?

 

What kind of system is it running on, as in CPU speed, RAM, and OS?

 

run CCleaner and get rid of the clutter i have had a similar problem and it was just my PC was stuffed with rubbish.

http://www.majorgeeks.com/CCleaner_d5125.html

http://bestsmileys.com/cleaning/5.gif