...because when I point and click, sometimes it just doesn't respond until I click a box 2,3,4 or more times! Somehow it has lost its sensitivity -- maybe a breakdown in the myelin sheath of the internal wires???

(Took me three clicks to get that smiley face.) Sheesh! The little hand is there and it looks like it's doing its job, but somehow it just doesn't "connect" unless I move the cursor and click around the area.
As far as I know it does its own virus scan every 3:00 a.m.
I got my brand new Windows 7 in the mail, but haven't installed it yet. Not sure if I dare! I'm bound to goof something up.
Would appreciate any input. Thanks!