Quirky Windows Explorer in WIN7

Whenever I open Windows Explorer in WIN7 and click on the cute triangle to open a folder, the entire left-hand display opens the folder and sub-folders, but it drops all the way to the bottom of the display window! This is the opposite of my XT experience, where when you expanded a directory, it went to the TOP of the display.
Even stranger, sometimes it only happens every OTHER time! This is simply bizarre and I'm wondering if anyone else has experienced this and if anyone knows of a solution (I'm sure there's an explanation, but I'n only intereseted in making it go AWAY!)
It's a clean install of WIN7 Professional in an AMD 3GHz quadcore 2GB RAM setup.