It's life is relative to the amount of charges it has had. Usually a sign of impending doom with these metel hydride batteries, is after it's fully charged, does the forth bar go out fairly quickly.
Going on it's age, you are getting near to the end of it's life, but it will still perform reasonably well, just loose it's charge quicker.
It should charge up fine, as metal hydride cells don't have any memory effect, but it may take a minute or so before the lcd's system, kicks in to charge the battery.