Another good first time sushi is yellowtail. It's mild and more firm than tuna and salmon. Red Snapper is also a good first choice but I think it's mainly a regional thing (I'm in Texas).
I've never been a big fan of rolls but the sushi place we frequent had a new one this weekend - Kudu roll. It had avacado, cucumber, yellowtail and garlic aoli, surrounded by the seaweed, rice and kudu - which is flying fish roe, as it turns out. It was delicious! I've been craving it all weekend.
Whenever I try a new sushi or roll, I make sure I have saki on hand because I've found if you try something that you can't stand the taste of, a quick bit of saki will overpower the taste and you'll be able to go back to what you DO like.