#2 first is no, once the quality or size has been reduced and stored that way, there's no satisfying way to get that size and quality back.
For number 1, don't just stick with Bridge and Photshop when attempting to open recovered files. Some software will be more forgiving when it comes to opening and displaying and if you can get one of those programs to open it successfully there's an excellent chance you can crop and resave or convert to another format and save and salvage at least some of those pictures if the visually intact protion of the photo(s) is worth saving.
Some of the programs I would try are Paint.net, Irfanview, FastStone Image Viewer, xnView...