Welcome (rock chalk?) As others have said, you'll need an inspection to register an out of state car in TX. Classic BMW is pretty good and Autoscope (independent shop) is pretty good too.
I don't think Uptown is too dangerous but like you said, don't leave valuables in clear sight and get wheel locks if you don't have them already.
Fun things to do aside from bars/clubs there's tons of shopping (Northpark mall, Galleria mall, West Village, Highland Park), there's tons of sports (Mavericks, Cowboys, Stars, FC Dallas), the horse racing track in Grand Prairie, Texas Motor Speedway, exercise at White Rock Lake/Katy Trail, Fort Worth stockyards. There's a lot of different things but DFW is very spread out so you'll be driving a lot.