I'm a bike newbie who knows little-to-nothing about bikes other than general upkeep. I currently ride a Mini-branded Dahon folding bike, which is fairly okay but slow/uncomfortable for longer rides. It also has a continuous problem with the derailleur not shifting completely, something I would definitely like to avoid. I'm looking for an off-the-shelf bike and was wondering if anyone could give me some pointers as to what brands and styles I should be looking at -- currently I'm considering the Specialized Vita and Ariel (lowest-end models), as I have an LBS nearby that deals almost exclusively in Specialized and provides lifetime tune-ups. However, I'm open to any other brand/model as long as it's fairly affordable. I plan on riding mostly on road for fun/fitness and light commuting, and I live in a community where bike thefts are moderately common so I want to avoid anything with too many removable parts and/or give me extreme paranoia about leaving it out-of-sight. I really appreciate any help I can get!