Closest thing to a Four Seasons you are going to find is either the Ahwahnee in the park (we just stayed in one of the cottages #703, and it was great) or Tenaya Lodge (but it's outside the park). Staying outside, you would be dealing with rides of an hour or more each way to get in and out. If you are going, you should stay in the Valley.
You should go. From a physical beauty standpoint, Yosemite is the most spectacular place I have ever seen.