I have a degree in Aero, and am working on my Phd in my spare time - I've also spent my entire career in aeronautics so it must have done me some good.
The courses are either 3 or 4yrs full time and phenominally hard work - because of the high entry requirements and the depth of the course they qualify you to work in most areas of Engineering. However, the degree alone won't usually get you a job unless you can show a couple of years experience in the field - so getting the first job can be a real struggle.
After that it takes about 4 years (if all goes well) to get a CEng and if you believe the Engineering Council figures (although personally I have doubts about their pay figure) the median pay for a CEng is 37k and the unemployment rate is 1.2%
Most Aero Engineers tend to specialise after a few years, for example in Stress-analysis, helicopter dynamics, flight testing, aerodynamics or whatever. Although it's possible to change (and many people do, I went from flight testing to airworthiness) it's worth aiming at a University which offers specialist courses in the areas you might wish to end up working in.
There have been discussions on this subject before, and it would be worth searching the archives for more info.
G