I do that here and I do not wait until Mother's Day either lol. If my wife is stressed or not feeling good, I will take the kids to a playground for a couple of hours. I will bring a cooler with water and snacks in it and just let them run wild. Plus I can get some homework for college done at the same time.
As far as gifts go, I guess that depends on what you ladies really like to recieve as gifts.
My wife is into scrapbooking, so if nothing else, I get her scrapbook stuff. She loves plants and flowers so I buy them when I can.
I may just give her a Wal-Mart gift card at times and let her buy whatever she wants to.
There is also a place here where you can go in and buy plates cups, ashtrays, knick knacks or whatever, paint them with your own design, personalize them for her and then they bake them in a kiln or something and you come back the next day to pick them up and she has her very own bowl, coffee mug, plate or whatever.
Sometimes a month or a couple of weeks before Mother's Day or her birthday I will write her a love letter everyday and give them to her on the special day.
Of course on her birthday or Mother's Day, I will do all of the cooking and cleaning for her.
Oh yeah, usually on Mother's Day, some of the cable networks will run marathons of tv shows all day and I will let her watch the marathon of "Ten Years Younger" or "What Not to Wear" or something that she likes.
Most of all, I try to go out of my way to let her know that she is appreciated and loved.