I have a 25 year old asphalt over concrete driveway with cracks and some deterioation at the edges. What kind of repair/replacement can you suggest?

After 25 years it has lived its life expectancy. You can patch with cold patch from a bag for the edges at the big box stores but the correct thing for many folks is to get 3 bids for a complete replacement. If you stick with repair your can fix the cracks with a asphalt caulk in a tube or a paste in a tub followed with a tar emulsion topping.

There are companies that do a great resurface and there are products you can fill cracks and do a coating.

Have you been keeping it up by coating it every few years?