Once had a harmless joke running through the office. Mail arrived, open this link, etc etc. The story was about relaxing in the office, and, here, have a coke. Then this file caused the cd to open, the punch line being "Here's your drink holder". Yuck, yuck, yuck.
Anyway, this program did do the trick. Here's the link to the current version of the program. Could this be the issue? Could you start up in diagnostic mode and examine all startup commands?
http://www.funnyhumor.com/downloads/34.php
g/l