Lagging Mouse

I am using Windows XP Prof. and a Logitech Trackman USB cordless mouse. When I am scrolling in a context menu (drop down) with my mouse(the ball, not the scroll wheel); for example, the right click on a desktop or when changing a folder view under "File" then "View as...", then I scroll down to my desired topic, the pointer has no problem getting straight to the selection, but the "shaded hi-lite" starts the hourglass loading for about 5-10 seconds and finally jumps down to where my arrow is pointed. It is as if the mouse stops to "think" or "check" something before continuing its movement.This is very annoying and it makes things slower. I have checked for newer driver updates, checked my mouse settings, etc., but nothing stops the lag. I believe there may be a program I installed that might be conflicting, but there is no telling which program it is. This just started happening a few months ago and I have installed many things since then. I do notice, however, that while in Microsoft Word, it locks up every so often. Probably due to the "periodic saving" being utilized. It may not be related to my problem. I plan to uninstall and reinstall Office XP, but doubt that will stop the mouse lag. Would a similar thing with that program, or other program, be causing my mouse lag?