If you are looking to carry a reasonable amount on the bike, you might want to look at bikes made specifically for commuting/touring. You would want a pannier rack and panniers too. You are probably fairly strong given your stats, but riding long distances with messenger or backpacks is probably not recommended. If you have the money, buy a good weatherproof set of panniers. On these commuting/bouring bikes the riding position is a bit more upright than a road bike and is more friendly to someone carrying extra weight than a road bike that is built for racing may be. Most are still quite speedy compared to a MTB. I bought a Mongoose Randonneur EX, which has the bonus of a fairly decent dynamo hub light. I know there are other bikes made by different manufacturers that are similar.
Transitman said:I'm in a similar situation... I'm looking to commute to work via commuter rail and bike home in the afternoon. The trek home would be about 35 miles. I've mountain biked a bit a few years ago but found I enjoyed road riding a great deal more with the MTB. I'm somewhat stuck on what type of road bike to buy, new or used, and specifically which manufacturer/model. A bit about me, 6'5" 200, 26yrs old. Used to be fairly active playing soccer 2/week, crew for a period, and biking a bit. Have not done a darn thing since moving from Boston To San Diego 1 year ago. Any pointers on bikes/equipment would be terrific.