Well, you're from California, so perhaps you won't be as horrified as we were about how $$$ everything is...we live in Louisville because it's the closest we could be to Boulder and not have to squeeze our family in to an expensive, rundown apartment in Boulder city limits. I still don't consider our rental house "affordable", but we could never buy a house here, so we just deal with it. Make sure you rent or thoroughly check out whatever town you pick--I don't like Louisville. It's safe (and the schools appear to be safe, and maybe "good", depending on what criteria you have for "good"), but there is no community here. The people are not mean, but they're not exactly friendly--one couple on our entire street has introduced themselves in 4 months, and we have a tough time even getting people to say hello when we pass them on the sidewalk.
We picked it (without seeing it, save a weekend trip here) because it was smallish (18,000) and bragged about its small town values, main street, etc. What I've seen is that everyone works, so it's desolate during the day, and the main street is a few restaurants and pricey shops--not the useable (grocery, hardware store, etc.) sort of small downtown I'm used to. There's big box stores on the edge of town, so it's not like we can't get groceries and things (though I usually go to Boulder), I just don't find it very community oriented. The rec center is nice, though, and a good value if you like to take classes, and there's lots of paths for walking. The library is new and they're very proud of it, but there's not a lot of books or good magazine selection--I end up ordering it all from the Boulder library. I don't have kids old enough for the schools, so I can't help you there.
I love the sense of community I get when I visit Nederland, but you'll have to consider the winter commute very carefully. Also, if you like a lot of "stuff" to do, you may feel isolated there. I'd move there if my husband could realistically get to work in a decent amount of time in winter, but it wouldn't work for us (there's a bus that goes to downtown Boulder, though).