I have an old (I think it's a 1992, based on some internet research) Trek 700 Multi Track Hybrid. Not a lot of miles at all, still riding on the OEM gumwall tires, with plenty of tread left. I'd like to get back into riding, but a bit more trail oriented. Instead of spending $$ on a midlife crisis shiny new mountain bike, I'd like to ease into it by making my Trek a bit more trail-worthy. The rims are marked Araya PX-45 700C and tires are marked 700 x 35C. Here's my question - can I just swap in a pair of more aggressive, knobby tires on the rims? Other than strength issues, is there any other difference between my rims and a mountain bike rim, like size or bead, that would prevent doing that? It looks like I have plenty of clearance for a wider/taller tire.
If this upgrade works, I might consider swapping in a suspended fork to replace the rigid fork. Again, is this "do-able"?
Thanks in advance for your help.