I agree with Giselle... Border Collies are definitely intended to be high energy, active, and driven to work. But, there are always extremes in every breed, and just like there are some BCs who are always going non-stop, there are also mellow BCs.

Definitely work on getting her into good shape, even if she isn't interested in playing. It's much *healthier* for her to get a good amount of vigorous exercise each day... it might require some coaxing, as it sounds like she isn't very play-driven.

Obedience work is reallyyy good mental, and even physical, exercise! Work up to looong down-waits, from a long distance, so she is running to you for each recall. Is there any dog-friendly places to swim in your area? Or any nice off-leash parks or trails? There are lots of exercise options for dogs that aren't into fetching or toys. If nothing else... I live in Sacramento, and my boys would be happy to play with her! ;D