Need Some Help with Dublin

Hey All -

I am going to Dublin and London in August. I will be in Dublin August 7-11 and London until the 16th (we are taking the boat over). I have already been to London and know what I need to do, but could really use some help with Dublin. We are staying in the Temple Bar area (I know - rowdy). I would like to take some time and go to Belfast - black cab tours. Anything you all can tell me about your hidden treasures/recommendations in Dublin? Anything that can make my life easier? Save me some money? Must sees outside of the normal tourist stuff (Jameson, etc). Thanks in advance.

In Dublin, don't miss Killmainham jail and the museum in the old Collins Baracks

Don't miss the Guiness factory tour. If you book in advance online you can bypass the queue, which is normally huge.

The Guinness Hop Store is the best starting point in my opinion and from there you can get a flavour of what you'd like to do.
I hate to say this but I'm from Ireland and don't really spend enough time in Dublin to give you much advice.
The national museum will give you a pretty rounded tour of Irish History in a short space of time. The National Gallery is also really worth a visit but aren't most museums and galleries....
Unfortunately my favourite - the Natural History Museum - has closed for repairs and nobody really knows when, or indeed if it will open again.
Sorry I can't help more.

I have not heard about the Killmainham Jail yet - I will be sure to add that to my "to do" list. Does anybody have any suggestions as to restaurants, pubs, or shops that are "must sees"? We are both 25 and would like to be around people our age. As we are staying in Temple Bar, that shouldn't be much of an issue, but what about in other areas? Grafton Street?