Dodgy knees - need help

Dear physio's of the world - please can you help me!

Last September I ran a 1/2 Marathon and since then I have have had real problems with both knees, although my right seems to generate more pain.

They are fine for everyday use. But if I do a long walk or attempt to run then really hurt and just give way from underneath me.

After a long wait on the NHS I finally have my MRI results - see below:

The specialist summised that I should never run again, never do impact exercise and that there is nothing more he can do for me! Surely at the age of 27 there must be more advice than this!

Right Knee
There is a signal intensity in the body of the medial meniscus which does not reach the articular surface. There is a small focal area of subchondral osseous oedema involving the medial tibial plateau. The appearances of the medial meniscus represents meniscal contusion.
There is patchy increased signal intensity involving both medial and lateral patellar facets suggestive of type 1 chondromalacia patellae.
Incidental finding of a small popliteal cyst.

Left Knee
There is a signal intensity in the body of the medial meniscus reaching the inferior articular surface in keeping with a meniscal tear. No displaced fragment seen.
Incidental finding of a bakers cyst.
There is patchy increased signal intensity involving the medial and lateral patellar facets suggestive of type 1 chrondromalacia patellae.

PLEASE HELP ME!