Hi,
if (more likely when) the chain starts falling off; you will have a couple choices. You can put the original 30T ring back and get a 12-34 rear cassette. Or you could throw on a Mtn bike crank that comes with a 26T small ring standard.

Lots of good tires out there. All depends on what works for you.
These work for me... http://rivendellbicycles.com/webalog...bes/10043.html