Correct that Microsoft is not responsible for Dell XP installs.  This sounds like a mouse problem to me.  Is the mouse working correctly otherwise and are you sure you're clicking lightly just once when dealing?  (Sorry if this is a stupid question.)   Another option:  Did this problem just occur for the first time?  If so, I would try running a System Restore point to a recent date when all was well.  And have you scanned for virus / spyware to ensure there isn't some kind of insidious little malware messing with your system?   

Took your advice and tried it all. ((Hhmmm...mouse problem.)) The mouse 'was' acting a little weird.. Thanks to you Europa, the dealing problem 'is' a lot better!!! Wow.