I have been using MS flight sim in conjunction with VATSIM for about 5-6 years.. When I started my flight training my instructor he was amazed and what I knew without ever really flying before. VATSIM is very cool, it provides Air Traffic Control for your flights by real people. With it you can be a pilot or you can be a controller. VATSIM is free. But like LA said, I would not use it for takeoffs/landings because it is nothing like flying the plane. But scanning the instruments and communicating with ATC on VATSIM might help you out.. Check it out at
www.vatsim.net