I am trying to decide on two different bikes to start trail riding. I have been idle from road biking for years and have been encouraged to take up mountain trail riding. I have the choice of a 2003 Gary Fisher Tassajara Silver series or a new Trek 4300 disk. I am 50, 5'9 185 lbs. As I mentioned I am new to trail riding. Just want advise on which bike to go with.