Mouse/Cursor Issues

So this is only an issue while I'm playing Wrath of the Lich King (not doing anything else)
When I mouse over something, it selects what is 2 or 3 inches to the right of it.
For example, when I went to click "enter world" it selected "delete character"- which nearly gave me a stroke.
It also doesn't allow my mouse to move any further than the hearthstone in my backpack.
This started happening after I was in Wintergrasp and my computer automatically updated. (Amazing, right?)
Any suggestions would be lovely!