What Bike to Use?

Bikes over the last ten years are getting cheaper and better. If you want to get into serious off-road riding you need to be looking at paying over £500 for a suitable bike. There is great value now in this price range, giving you Shimano or sram gears and a lot of alloy components. The way bike manufacturers are going lately is towards weight saving. With many of the top range bikes now weighing under 23 pounds, and the cheaper bikes under 29 pounds.
One important thing when buying a bike is what size frame you should get. Unlike road racing bikes mountain bike frames need to be smaller to give you clearance when riding off-road. The best way to do this is visit your local bike shop and try a few for size. The shop will also be able to advise you on the best fit.
People go on about needing suspension on a bike, but I feel a beginner should start on a hard-tail bike with front suspension to help hone your skills. They also tend to be lighter and easier to maintain.