Whatever your sport, your training should surely be geared towards that sport. Therefore if you're a runner, the bulk of your training should be running. You can't run every day, but if you're training for a race, then you should be going out 3-5 times a week. Still go to your exercise classes, but leave them for the days when you're not running. Nothing wrong with doing something different, e.g. strength training or exercise classes as it helps keep your fitness levels up while using different muscle groups and therefore enabling the muscles used in running to recover. I can understand you saying that you find running boring but for me, going out to train in the open is more enjoyable than training inside, unless it's pluting it down of course. To make it less boring, get yourself a running buddy, try using different routes or maybe even do some "quality" sessions e.g. intervals/hills/speedwork (you can find ideas for such sessions on here, on the FIRST site or a site that I stumbled upon recently called "Running Planet".
If you're doing those sort of times in training on undulating courses, then you should have no problem doing a sub-1.40 half marathon. If you gear your training specifically towards it, you'd probably knock the best part of 10 minutes off that. People always go faster in races than training. I wouldn't be surprised if you could do a sub 40 10k and maybe even a sub-19 5k race.
Rudders, a word of warning. I had similar symptoms about 7 years ago. It started when I tweaked something in my knee while running up stairs at work. It was a bit sore for a couple of weeks or so, then it felt ok again (or so I thought). Fast forward 16 months and many miles later, the tendon snapped. My initial pain was due to straining the tendon (didn't know it at the time). Sometimes on runs, my knee would lock momentarily. Each time it did, I was putting more strain on the tendon. It might just be a bit of tendonitis and hopefully, rest and physio will sort it out. All the same, get it checked out as a precaution.
Haven't had the chance to read all of it as there's quite a lot to read. You've obviously put a lot of work into it. When I get the chance, I'll look at it in a bit more depth. Just one slight problem. The links in the main body of the message don't work. They just take you to a non-existent page on the RW site with the message "Page not found". The link at the bottom of your message works though.