Refinishing Oak Cabinets

Hi, I have 20+ year old kitchen cabinets that need updating, but I cannot afford to replace them right now. I wanted to try to refinish them with Minwax PolyShades, but after visiting that thread and reading all the negative posts, I am convinced that is not the way to go. Soooo, I need some advice as to how I can give these cabinets a face lift. They are of a meadow oak (medium shade) finish, some are in good condition and I could probably just lightly sand and re-polyurethane and they would be fine, but others that have received much more use probably should be sanded and re-stained. Can I use a gel stain if I sand the surface first and then use a clear poly over? Do I need to sand down to bare wood or can I just sand enough so that it will hold the stain? Or should I just use a conventional stain and poly afterward? I also plan to swap out all the hardware with new and then add new cabinet pulls to update the look. I really need to do this so any advice you give will be greatly appreciated.