Sun..

In any design if there are specific parameters of any sort that must be recoverable through a RESET or power cycle then by all means these parameters must be saved in a EEPROM, battery powered SRAM, or in a FLASH card.

In general I have found little or no need to save all SFR and PORT register values through a RESET. You should think of a RESET as a "beginning" point for operation of your program. Then if a few port line states must be configured according to a non-volatile parameter someplace then read the parameter and set the port bits accordingly.

You should not think of a RESET as something your hardware has to contend with as an inconvenience. If you are having "accidental" or "unintentional" RESETs then the hardware needs to be redesigned to the level necessary to attain the expected level of reliability. The RESET should be saved for recovering from things over which you have no control such as a loss of power line voltage or the exposure to a huge ground surge from an act of god such as a lightening storm. The other main use for RESET is for when you want a new "beginning" intentionally.

Michael Karas