Hi
I had a similar problem where a particular window would not display correctly (when a script fails on bitmap synchronization and there is an option to accept OK or Cancel - these options were hidden outside the displayed window!
This occurred when I upgraded from 11.04 to 11.52 - I uninstalled loadrunner before installing new version - however, I think the uninstall is not clearing everything correctly.
The only way I got round this was by installing 11.52 onto a new desktop - no longer a problem! That window displays correctly!
So - have you upgraded recently?