Dennis the Menace always strikes me as a central defender. Don't reckon he's got much page to be a box-to-box midfielder, and given his sneaky, conniving natures, I don't think he be that fussed about tracking back to help out when the rest of the team needed it. He's got the selfishness to be a 'fox in the box', but I'm not convinced this would be his best position.
There's a thread in here somewhere – "name your cartoon/comic book XI" or something...