First of all, you need to disable it in the startup menu.
I recommend Startup Inspector for that.
Startup Inspector (manages startup menu – helps you identify aps in the startup menu so you can disable unnecessary programs from running in the background when they are not needed)
Startup Monitor (a small freeware ap available on the same page to notify you and require your permission for any program to add itself to your startup menu)http://www.windowsstartup.com/download.php
After that, if you want to uninstall it completely use add/remove programs in the control panel.