I'm 46 and suffer with severe back and neck pain and my weight is increasing and I wish to take up exercise

Have you tried aquatic therapy to start? Also for you back and neck pain, consider trying chiropractic treatment. It is effective, not painful and no side effects like medication. Plus there are many different techiques and therapies that may be helpful. Finally, physical therapy may also be able to help you. They can help design a fitness program for you that will work with your body and abilities.

Research has shown that patients who suffer from chronic neck and back pain do well with an exercise program. Here is a great blog post about this: Treatment of Chronic Neck Pain Through Physical Exercise