If it doesnt' fit, though, it *will* sit in the garage 'cause it won't be fun.
If it's a Wal-Mart special, then when things wear out it's time for a new bike ;(

Sometimes you can get something nice used - our local bike shops do trade-ins.

Fit & comfort is the thing - whetehr road or hybrid or whatever. (I have yet to find a road bike I'm comfy on, and since I go fast enough for me on my hybrids, I don't look too hard).
http://www.champaigncycle.com/frame.htm has a button ont he top to go to "choosing the right bike" that has some good ideas for framing your thinking. (It's a *little* dated with some of the links but theideas are good.)