Bike Forums - New guy

Hello everyone. I am a 31 year old married guy in northwestern Montana. My wife and I have 2 boys, one is 3 years, the other is 3 months. I haven't ridden a bike since I was a teenager when I used to goof around with freestyle bmx. This last Saturday I pulled my wife's old bike out of the rafters of the garage and took a lap around the neighborhood just out of sheer boredom. That reminded me how nice it is to ride a bike instead of drive everywhere. I really enjoy slowing down and taking in some more of the scenery, while covering more ground than just walking.
So anyway, a trip around the neighborhood turned into a trip to the local bike shop where I came home with a Giant Rincon mountain bike. I plan on getting to the point where I can use my bike to commute to work 5 miles each way. 5 miles isn't much, but the trip home after working in a 100+ degree sawmill for 12 hours is mostly uphill and I know I'm not ready for that yet. There are also a couple of ski resorts up here with great trail systems that I want to take advantage of when I'm ready.

I haven't touched a bike in 12+ years and am 70 pounds heavier now too. Just realizing how fat and out of shape I really am. Hoping to pick up some good knowledge here, don't be ticked if I spend most of my time lurking instead of posting.