The Tir Na Nog is a narrow dark bar.
Foodwise, the Fish and Chips are the best on the menu. I also recommend the Stake Tips.
Nearly everyweekend there is live music. One problem I have with the live music is that the bar is quite tiny so the noise can get a little overwhelming.
The atmosphere is very casual. I have seen Irish immigrants playing cribbage and a woman's dog walking club drink there. The beers are all around $5, Pabst Blue Ribbon is usually on special for under $3.