Can you open any of your backups? Can you save the layers/channels searately? What format are you trying to save the files as?
How much RAM do you have, and what are your scratch disk and memory settings? Are you working with more layers than usual?
Have you installed any new filters recently?
Are you using TrueType fonts? Are the required fonts installed on this computer?
Which version of Photoshop is it? Mac or PC? If it's Mac, go to
http://kb.adobe.com/selfservice/view...ernalId=331627