Originally Posted by
dlittledlite
I am experienced in many bike repairs, however, I don't know about maintenances, listed by savethekudzu, like drivetrain cleaning and wheel truing. I am very confused about how many speeds I should have... 10, 12, 18, 21,26... Oiye...
Check out the book linked to from that post - it explains much. Also, Sheldon Brown's site.
Number of gears: I think as long as you have a wide gear range, you should be good. No singlespeeds if you have hills unless you already know you must have a singlespeed. Most entry level bikes have 21 speeds; for my own commute I wouldn't want under 7 speeds.
Maybe someone who owns multiple bikes could comment on gears, though.
Where are you located? What's the climate and traffic / road conditions like?