Thank you so much for the responses, I love this forum!
I had a look at the ignition system... the leads were all ok, the spark plug gap needed adjusting and the plugs themselves cleaning, did that then had a look at dizzy. The cap was really dirty inside and the points had slipped quite considerably (I only checked them the other week as well!)
So now it will start and the idle speed is staying a bit more level, though it does still sound like it's hunting.
Thanks again!
