Thanks, everyone. I had no trouble getting a printed boarding pass at the airport. The only trouble I had was when I tried to check my parents in from my computer, it let my father check in, but it kicked me out when I tried to check my mother in. When we got to the airport, I stuck my DM card into the kiosk & it pulled up my parents' itinerary, which was on a totally different PNR. But that was also easily resolved at the airport.

I think the web check-in helped tremendously. F was full, but the friendly gate agent told me to "definitely check in with her before I boarded." I told her I was going to the club in the B concourse, and sure enough, about 15 minutes later she had the club page me to give me my new boarding pass.