wandering cursor and odd drop down menu problem while typing

when i type, on some keystrokes when i use the ****ft button it will pull a 
drop down menu- the one where you can choose copy, paste etc.  i have no
idea 
why.  it just started doing it one day. 

also, now, after i took the pc in to be looked at and they did 
troubleshooting and found nothing wrong.. i have a new problem.  my cursor

arrow wanders sometimes drifts sometimes zooms around my page.  it is
doing 
it in ie but also firefox.  so i assume these problems are both xp
related.  

the list is so long for choosing a discussion group i didn't see xp yet.
i'm running xp on an hp.  firefox 2.0 and ie 7

anybody have any ideas where i should start?