To remove add-ons in XBMC, please follow these steps:
Start XBMC (!)
Scroll across to, and click on, the System menu
Select add-ons
Select enabled add-ons
Select video add-ons
Now click on the first add-on you want to remove, and select uninstall
Repeat this for all add-ons you want to remove
Return to XBMC's homescreen and click the power button to shutdown
Restart XBMC and check there are no add-ons left that you don't want.