Firefox 3.5.6 Uninstaller not working

Question

I want to uninstall Firefox 3.5.6 in favor of Opera 10.10. However, I've went into Control Panel > Add or Remove Programs and tried clicking Remove from there, but nothing happens. I go into the Program Files for FIrefox and find the Uninstaller folder and click the helper.exe found in there. Still, nothing happens. Is there some possible way to uninstall Firefox without screwing up the rest of my computer?

Computer is a EMACHINES T2482: http://emachines.com/support/product_support.html?cat=Desktops&subcat=T%20Series&model=T2482 RAM has been upgraded to 1 GB PC3200 DDR, GPU has been upgraded to 128MB GeForce 6200, HDD has been upgraded to 160 GB, PSU has been upgraded to 350W and Floppy and DVD Reader have been disconnected from mobo and power. OS is XP Pro SP3

Answer 1

First reinstall Firefox 3.5.6 and try uninstall again, if this doesn't help, use Revo Uninstaller:

Revo Uninstaller helps you to uninstall software and remove unwanted programs installed on your computer even if you have problems uninstalling and cannot uninstall them from "Windows Add or Remove Programs" control panel applet.