The St Regis Dana Point is a very nice resort. The rooms are exceptional. The grounds are beautiful, but if you want ocean vistas then you should go to the Ritz.
Had dinner at Motif and was thrilled. The service was excellent, the food was superb and the wine list extensive.
I didn't get to play golf, but I walked a couple of the holes and it looks impressive.
I have stayed at the Ritz (just across the highway) and comparing the two:
Rooms: St Regis (significantly larger and much better looking)
Landscaping: I give the nod to the Ritz. Ritz is right on the beach and has beautiful views.
Service: Ritz; St Regis needs to work with their employees while the Ritz employees are always smiling and welcoming
Food/Restaurants: They are both great
Pool(s): I think the Ritz because they have more variety
If it is your first stay at either of these properties, I would say go for the St Regis (the rooms are so much nicer) unless you can get the Ritz for a significantly lower price (I recently had that opportunity as the Ritz was running a package promo).