I started with a 42/16 as well. I'm 44, making progress shape wise. Hey, there's people at work who at least look like they might be in better shape who wonder how the hell I ride 30 miles to work. pici's comment that the 42/16 is quick in traffic is actually very important. If you're commuting you need something you can repeatedly haul up to speed from red lights and stop signs (I hope you're stopping at stop signs and signals - especially in front of motorists - and helping our rep). I have a couple significant, extended climbs on my commute and the 42/16 is the tallest gear I can use right now.
DanO