I'm going to echo the beer suggestion. Should be some good lagers at an Irish place. Guiness may be too heavy for someone who hasn't drank before, I was never real fond of the taste myself, but a Harp would be tasty. As for the other stuff, your friends will likely buy you a few shots during the evening but beer is a good base to stick with. FWIW, I can't stomach the taste of tequila myself - comes right back up.