For some time now, I have observed that when performing a search, which involves "Wikipedia, the free encyclopedia" using Google, I find that I am re-directed to the ask.com search engine.
I haven't run into that ask.com with Norton but it is a very common add-on especially with certain Adobe products.
Since I don't have it on this machine I can't be certain but check under Tools on the Menu bar of your Internet Explorer browser (if you don't see that menu bar press the ALT key and it should appear for this operation and look for Manage Add-ons.
If Ask.com shows then highltight the line and click on Disable down at the bottom and OK your way out.
If that works but it comes back when you restart your computer look for a reference to it in StartUP.
Check tht out -- or if someone can give you more specific directions follow them -- and let us know what happens while I look for something more specific.
Open the Norton Toolbar settings from the dropdown button on the toolbar and disable Norton Safe Search, which is the search component (provided by Ask.com) included with the toolbar. Set your preferred search engine in the browser search bar.