Try using Revo Uninstaller. Even if it can't uninstall the application normally, it will force it to uninstall by wiping out all traces of its presence from the system.
After that, try running AdwCleaner to make sure that there are no leftover rogue registry keys or toolbars in your system.
If you still have problems, reboot the computer then press the F8 until the service menu appears. Select Safe Mode and then uninstall the application. The restart is caused by a conflicting system files. If you use Safe Mode, Windows will load all the base drivers.