What if, right after you made the agreement, we had world-wide nuclear war. Then what?
"No ray of sunshine is ever lost, but the green which it awakes into existence needs time to sprout, and it is not always granted to the sower to see the harvest. All work that is worth anything is done in faith." - Albert Schweitzer
Absolutely, certainly up to the point of having a lifespan in the range of thousands of years, at any rate. There are so many things to see and do, but most of all the part that would intrigue me is to watch civilization evolve (and devolve, and reevolve). Getting to be a part of that, even primarily as an observer, would really appeal to me.
Also, of course, is the time to reinvent myself as many times as I'd care to. It wouldn't all be wonderful - seeing people you love grow old and die, most of all, but that's something that we all learn to live with anyway, and you'd get to carry memories of them too.
I most definitley would NOT... the very knowlege that some day the sun is going to swallow the earth makes the prospect unpleasant.... and without guarenteed healing abilities you could end up like in Death Becomes Her
On top of that, where would the thrill be to risky activities if you were assured that you wouldn't live?
Human beings make life so interesting. Do you know that in a universe so full of wonders, they have managed to invent boredom? -Terry Pratchett