From someone whos been there and done that. Trust me if your asking yourself that question, have a massive rethink!! Sit yourself down, find out what you want to do, speak to people in that field, then follow the path to the top.
Too many people dont and just waste time doing a degree to fill in a gap in their life (like me) and come out with 12k plus of debt and a piece of paper that really means jack for the career they've chosen.
Hope that helped!!!
Maths or science, apparently there is a huge shortgage of graduates in these areas. Shortage = better careers prospects.
However, you do realise that university is not compulsory don't you?