Originally Posted by Telix
You can also get a flip-flop wheelset (the popular Mavic CXP-22's laced to Formula hubs for $140 or so are a great beginner flip-flop) and run two different cogs for different situations if you were so inclined. Get a 48 tooth up front and run an 18 and a 16 in the rear.
+1, that sounds like a great pair of gears although I would run a 47 up front for much better skid patches---18 and 16 versus 3 and 1---yikes! Anyhow the basic idea is sound, a 70-ish inch gear and 75-ish inch gear will get you through most stuff and give you a good idea of what you like. FWIW I do long road rides and about town cruising and love 70.