Week in Ireland: What to do?

I'm spending a week in Ireland with my two older siblings and my 66 year-old, Rheumatoid Arthritis-stricken, heavy smoker of a mother (whose two previous visits to me in Europe have ended up in minor disaster--(1)hypothermia/pneumonia (2)her going missing for a couple of hours due to getting on the wrong train without a phone).  At the very least, I'm a little apprehensive, and if I had complete control of the visit, we wouldn't leave the cottage.  However, for some reason she insists on exploring and enjoying the country while she has the chance.  Does anybody had any suggestions for a mobility challenged person with three overly anxious adult children in tow?

We will be spending the final week of April based in Clifden, and we will have a rental car so are looking forward to taking day trips.  We've agreed that we want to go horseback riding and visit the Giants Causeway, but that's all so far.  From my experience traveling with my mother, I tend to go for the nerdy historical stuff, whereas visually and paletably appealing attract her.  I'm think maybe visiting a castle would be a good compromise. 

Cheers!

Powers Court is amaaaazing and so worth the visit :-)

So how long will you be in Ireland?  Will you be staying in different places or just Clifden.  You probably already know this, but The Giant's Causeway is pretty far from Clifden!  If you're going to be staying for a few days in N. Ireland near the Giant's Causeway, go see Dunluce Castle, it's fantastic.  The Antrim Glens are really beautiful.

If you can get down to Co. Clare from Clifden (Galway), go explore the burren.  The landscape itself is beautiful, and there are loads of ancient sites to see like Caherconnel Stone Fort, tombs, dolmens, old churches in the area, etc.

Well it really depends on where you'll be starting your journey.  Unless you'll be in the North, a day-trip to the Giant's Causeway will be a VERY long drive.  If you'd like to drive through Joyce Country it would be well worth it because some of the scenery there is spectacular.  If you happen to be in the East at any point, check out the Wicklow Mountains and Glendalough.  If you want to go to Newgrange get there fairly early in the day to avoid the tours being sold out.  They take you by bus from the visitors centre to the monuments, but there is a little bit of a walk to get to the bus pick-up station.  The Hill of Tara and the village of Slane are nearby as well.
General advice for driving in Ireland: many of the roads aren't very fast and some may even be poorly marked. When we drove around it took us a good four days from starting in Belfast, going south, west to Galway and back to Belfast. Driving through Galway, Connemara, up to Sligo and back to Belfast took us nearly a whole day. 
If you plan to explore Connemara, stock up on stuff to eat and plenty of petrol, there isn't much at all in the middle, just road and mountains, but it's GORGEOUS!

Hope ya have a good trip!