Fly to Cork and get yourself down to the Crosshaven and Kinsale neck of the woods. Lovely countryside, stunning coastline and, when I was last there, the grub was gleaming! Failing that, head north and do a Battlefield tour of all the old Op BANNER sites. I've been meaning to do that for years. Whatever you do, drink plenty of the blackstuff and enjoy the Craic.
There are people in Belfast who specialise in weekend breaks... of the knees, arms, legs, fingers etc... So I'd avoid them too and head to the glorious North Coast - it shouldn't be too touristy now as the season has just ended. Miles and miles of sandy beaches and ruined castles and weird rock formations and the world's oldest whiskey distillery
Failing that, The west coast of Donegal is quite nice too.