Start Button menu disappears

The menu that opens when I hit the Start has begun blinking off immediately
on opening. This happens whether or not I even move the cursor. It seems to
blink off the first time I click Start, but stay stable if I click it
another time...or another 3 or 4 times. But if I go elsewhere on my screen
and then back to the Start button, I start all over with the blink-out.

Anybody have a clue? I'm running XP Media Edition, which my geek thinks is
vastly inferior to XP Pro, on a Dell Dimension 9150.


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