You're spoilt in Galway, small town but relatively great food offerings: three places in Galway I've heard about lately are Ard Bia cafe, Kai cafe and a place I haven't been to: Anair restaurant whose chef Enda McEvoy received 'Chef of the year 2011' in Ireland - check it out on the web, looks great and a friend who's opinion I trust raves about it. If you're lucky, it'll stop raining.
As for Cork, Nash 19, the Crawford Gallery Cafe and Cafe Paradiso are all great. Cafe Paradiso is one of the best veggie restaurants on this side of the Atlantic. The English Market is good fun: sure, it has all the usual mainstream stuff but also local cheeses, terrines and charcuterie, great seafood, organic veggies, and pigs feet for the local crubeens! Try a spiced beef roll there in the stall opposite O'Connell's fishmonger.
In Kinsale its the Fishy Fishy, the Lemon Leaf cafe and Max's that I would recommend. The Fishy is resting on its laurels a bit and some items are fairly pedestrian but I've had some of my best fish meals there. The little cafe he has does great fish and chips too.
In Kenmare, avoid the Park Hotel, €9.50 for a cappuccino and a mince pie, ahh Celtic Tiger where are you now?
Sheridans Cheesemonger has (or had) a nice little wine bar upstairs where you could sample the cheese and charcuterie
Outside town in Kilcolgan there's a place ced Morans on The Weir where can enjoy soome very good oysters and other seafood
I've heard from friends that Eight Bar was good but I haven't been myself
The English Market is a great place to check out local produce (otherwise I was generally disappointed)
In Kinsale, I thought Fishy fishy was good
There are also a few smokeries in the direction of Cobh which might prove interesting
A colleague reckons that Campagne restaurant is excellent
Must admit, I was also disappointed with the English Market. The way it's sold, I'd expected something more of a gourmet shopping experience. But, in fact, quality and variety was no better than you get in a British market hall and, often, worse. Lunch in the cafe was good though.
No foodie hints, but it is the best time of year to visit Ireland [not crowded]. Well, take that back .... If you stay at an Irish B&B, the breakfast in the morning are usually both filling and generally have coffee! Further, if you are staying at B&B's,then do note that some gentle negotiations on price is generally allowable ....
We spent a week in Kinsale in 2008. Places may have changed since, or may have closed - so I'm not keen on offering recommendations.
The town styles itself as the "gourmet captial of Ireland". Frankly, it would be depressing if that is true. It isn't a gourmet anything, IMO.
The place that gets all the play is Fishy Fishy. Beats me why that should be the case - our meal there was very disappointing.
If still open, Max's was a stand-out and the only place that I'd be happy to recommend.
A week was actually a perfect time to spend in the area. Good base for day trips; some pleasant walks and, when it wasnt raining, just sitting in the garden reading our books.
Blue Haven was not at all decent. Cooking was quite poor with some elements being just nasty. We considered it very much a tourist trap for American visitors (I gather it features/featured in their guidebooks)