I have watched How to Train Your Dragon, so i think i am good prepared :D

Turn tail and RUN! Possibly try to hide underground or in a fortified structure

I'm one, so I'm kinda safe I hope :D

I'd call the cops :D

Shit my pants and wait for death.

I'd try to befriend it, it's not that I have many dragon friends anyway...

Lay down and start to cry xD
Edit: or try to hug this dragon xD

I'd probably panic and then die. :D

run/hide

Run and hide. I would use my fists if i lived in Skyrim.

I've trained all my life for that moment...

View attached image.

I'd yell DRACARYS! Sit! and show him who's boss. :3

Hide, then freak out that there are really dragons! ;D

I'd tear him apart with a fus-duh-rah!

Try to make friends with it. And then probably be eaten :)

I'd love to say that I could slay a dragon and be a hero but I think I have to leave that one to the military.

Try and run. Realising it is useless, I await my death.

"Wait! See this sexy dragon over there? I got some tips for You and she's yours forever..."

RUN

Roll a d20 of course. :)

smile-- cuz they are ficticious

If all else fails use fire.

I would fus ro dah the fuck out of it.

1. hide underground,
2. cover myself in mud,
3. wait,

then

4. make a bomb
5. prepare some sheeps, pigs, etc,
6. cover the bomb with above animals
7. fire one sheep and or / pork to make a meaty smoke
8. hide again
9. win

Dragons are intelligent, and I wouldn't do anything to anger one (at least, not without being incredibly prepared), so this has to be some kind of misunderstanding. Maybe we can talk it out? It wouldn't hurt to be on good terms with a dragon.