TP has *some* large lots, mostly in the historic district or along Sligo Creek Parkway itself (which would be awesome for kids!). The commute from TP to Rockville would suck if you plan to take Metro (since you essentially go all the way downtown and back up, on the Red Line), but the people I know in TP who work in Rockville just drive (their Priuses

) and it's a lot quicker.