irratick cursor in excel
 

I have MS Office 2003 sml bus ed. OS: Windows XP Prof. When i pull up excel
and start to work, the screen dispays a heavy crosshair cursor symbol. When
I go to move the cursor it continues to paint whatever direction I might have
it in. In other words, this cursor just keeps moving on its own, it's wild.
At this point I can only go to Windows Task Mgr and end the excel task. I
just have the feeling I did something stupid but I can't seem to solve this.
Help would be much appreciated.