Oh lol 10 dragons is really too much. I remember playing JG2 Tegel Manor and only guy that was a real problem was a wizard with delayed blast fireball, though he was just there with some scrolls and not really important for the story still after many tries I couldn't kill him without him damaging the party so avoided him.
Anyway it seems that good tactic is to start with a little higher character level then needed as most of the modules at the end pack some seriously tough fights which I couldn't sometimes pass because of starting with low or normaly needed level of characters, also normal fights go much faster though that challenge factor is a bit down and games can look a bit more easy then it should.
For me now, I am doing the Castle Greyhawk, and though it is good it is one of those megalo dungeons where You can meet almost any monster and well up till now I have met ninja turtles and some others lastly some dungeon designer asked me to pick up a fight to help him with dungeon setting, so there were 6 red dragons without treasure, but also a beholder with bunch of gems, beside those minor like kobold with +1 dagger and graz'zt with 1pp. I tried beholder that and finished turned to stone and well just reloading seemed a faster route
Anyway I was thinking about writting a review for this module after finishing it, which I hope I will. Good thing is that it is actualy a complete Castle Greyhawk, the not so good is probably that I am somwhere in the middle about lv5 or six and I think there are at least 10 levels of it

still lots to go probably

. Also I was thinking how long would take me to complete that module playing it on table top and I think it would take years

so I guess I should be happy after all while playing it.