I'm with Faceman on this one. If she is lame due to an injury not something genetic I would breed her. Maybe wait until she is walking better.
I have a mare whose hooves were mangled in a bad trimming job the vet said it would take a year to heal. She was given to someone and they were riding her within a month. Now she is probably lame for life.
I intend to breed her if she is not in pain after giving her plenty of time to heal and getting corrective shoes every 4-6 weeks. Shalom