Don't be nervous about the asvab, the average person does just fine on it.

I grew up an army brat, so joining the military myself wasn't such a big choice. (Of course, this was back in the early 90's, before all hell broke loose.)
I took the asvab in high school, and scored well. I never studied. I had it in my head that I wanted to become a state trooper once I got out, so I picked Military Police as an MOS. They told me it wasn't available, and I told them I wasn't signing anything until I got my choice. It's amazing how quickly a class spot opened up for me.

I was not married when I went in, but I did get married while I was in. I didn't get shipped overseas, though I wanted to be. (Wanted Germany, I miss it.) I spent all five years at White Sands Missile Range, NM and then came back to WV when I finished my duty.

As far as picking an MOS, take a look at the list, and think of the things you enjoy doing and what you might like to do once you get out. You'll definitely pick up some valuable job skills that will aid you in your future endeavors. It wouldn't hurt to talk to a recruiter if you've got questions - they're there to answer them.

Good luck!