There would be just one condition with me living forever; I would want someone to live forever with me.
Growing old is a pain in the butt. I mean, it has it's ups and it's downs. Watching members of your family pass-away. Watching the world change. Watching life as it goes on with or without you. All those things are hard enough to watch. But the journey is made worthwhile when you're sharing it with someone.
So, yes, I would love to live forever. But I'll need someone to share it with me. At least, if family and friends passed on, the bitterness of their loss would not be as great knowing I still have that "one" with me, by my side at all times, helping me deal with it all.