vauxhall key fob?

our key fob has been playing up for a while but yesterday it would not open the car for a long time.once it did open we didn't want to lock it again.the manual key only unlocks the drivers door but is it ok to manually pull the door knobs up or will this mess up the electonics?we couldn't see how to open the key fob to replace the battery.does it have to be a vauxhall garage to help us or can any other garage help