Uninstall/reinstall your Adobe program. It is probably the Reader. You can also stop its automatic updating behavior by (in Reader) going to Edit>Preferences>Updater. You also need to remove two entries in Startup. I do this by running regedit but you may feel more comfortable using the System Configuration Utility instead.
Start>Run>msconfig [enter]
This brings up the System Configuration Utility. Look on the Startup tab and find the probable culprit. Uncheck the box next to its name, Apply and OK out. You don't need to restart immediately, but the next time you do you'll get a dialog saying you've used the Utility. Just tick the box that says in effect, "don't bother me about this again".
Important - Do not use the System Configuration Utility to stop processes. Instead, use Start>Run>services.msc [enter] and do not stop any services unless you really, really know what you're doing.
How to Troubleshoot By Using the Msconfig Utility in Windows XP - http://support.microsoft.com/?id=310560
The free Autoruns program is very useful for managing your Startup - http://www.microsoft.com/technet/sysinternals/default.mspx
MS-MVP - Elephant Boy Computers - Don't Panic!