>Cross Training>Several 5k's done, am I ready to move on to a Tri or 10k?
I would say that you should go for it! I started running in October of last year with the C2K program and once I was able to finish a 5k I moved on to the 8k training for an 8k race. After that I did the sprint tri training and completed a sprint tri over the summer. Now I have moved on to the half training.
For me, I need a program with a training schedule to keep me motivated. I am a slow runner, but speed is not my main focus.
Concept2 - Marathons Rowed April & May 2013