Two years and two puppies later, I rolled up my area rug and found the
hardwood floors seriously darkened from prior puppy accidents.  I
thought I only had to cleean the rug, apparently I was very wrong.  So
now my question is, without refinishing my hardwood floor or
restaining or painting them, is there some other way to lighten or
darken the floors to minimize the effect of puppy damage.  I am only
looking for a temporary fix to take me through the holidays.

I'm a volunteer with a pet adoption organization, and the best thing I
know of for a temporary fix is PAWS ("Pet Accident Washup Solution"):

http://www.bio-ox.com/products/paws.htm

This product is not likely to resolve your problem entirely; you will
probably have to sand the stains out eventually. But PAWS can make a
dramatic difference.

Thanks. I'll give it a try.  Unless I get a better answer, I'll pay
you for response.

thanks