Originally Posted by
Korina
Throwing in my vote for vintage steel mountain bikes... they're very versatile and quite inexpensive. Also, they'll take actual wide tires.
I agree 100%. It's what I did, too.
Get a high quality, steel frame (no suspension). The cantilever brakes will do everything you need.
Add a comfortable Brooks saddle (B67?) to go with the upright bars. This is the best position for negotiating traffic.
Ditch the knobbies and get some wide Schwalbe Kojak tires (smooth tread).