First close all browsers. Navigate to your add or remove programs page in the control panel. Find conduit on the list and uninstall.
Open your browser again, navigate to your plugins page in the settings. Remove conduit from the plugins. Now navigate to your normal settings page and you should a spot for search providers. Remove conduit from there as well.
Now you're conduit free!
Be a little more careful when installing programs in the future, and always click custom set up when you can, to avoid installing conduit again. Many software makers like to sneak that kind of crap in there on you.