I haven't read every post, but I agree a lot with MsElle07 (hi!!! How's your little one doing? Two already, hard to believe!!) OK, back to our regularly scheduled post...lol
I live in Derwood, which is between Rockville and Gaithersburg and LOVE this location. We are a hop, skip, and a jump away from 370 (that leads to 270, that leads to everything) and also semi-walking distance to the metro. My DH takes the metro to DC and either rides his bike, drives his scooter, takes the bus (bus stop right outside our door), or walks to the metro everyday. Our rent is $2200 for a single-family home with 4 bedrooms, 3 full baths, 2 living areas, deck and screened porch, 2-car garage, and nice-sized back yard (just to give you an idea of what $2200 can get you). When we were searching for a place to live there was no shortage of nice homes in this price range (2 years ago) and even more probably available now b/c of the buyers' market. The house next door to us is renting for the same amount and I think it's bigger. I would HIGHLY recommend our area (and I'm not biased...I don't really care for the DC metro area in general, but if you have to live here, this is a great neighborhood).
We used to live in Silver Spring and absolutely hated it. Traffic was a nightmare--which is the case most everywhere here...I'd pay more money for rent to be out of that mess!! We paid $1500/month for our much-smaller, no garage, older house there. I agree, though, Silver Spring is huge...ie: we lived next to the Glenmont metro station. Not the best neighborhood! I wouldn't have walked down our street alone at night.
As far as total cost of living, my DH makes a little more than your DH does currently, but we've been living off his single income since we moved here and he was making much less. You shouldn't have trouble living off $95K.
There are TONS of moms groups, playdates, county-sponsored classes and activities, etc. around here. We have an AP group you can join; we have playdates every Friday and a discussion topic the first Friday of each month. If you look on yahoo groups you'll find a constant stream of new moms groups starting up, all with different niches/interests. Lots of volunteer opportunities, too. PM me when you get here and I can give you all the info for the groups I belong to.
I agree with the others that you probably don't want to live too far from your DH's job unless you live very close to the metro--and even then I'd highly suggest living on the Western end of the red line--b/c of the commute. The metro is not as reliable as it could be.
HTH! Welcome to the area! BTW, my DD is just a little older than your DS. We need a few more boys around here...seems we're all having girls only! lol (I think there's something in the water!)