Personally Ive got no problem with ageing being optional. Why should people die of old age if they dont want to, and if it is medically possible? In ancient scriptures we often find mentions of people living for 100s, or maybe 1000s of years, so even if it is not true, this concept of living for a really long time has been alive forever.
Scientifically and philosophically, we can live for ever if our consciousness can survive without a body. Even in terms of body, old age happens due to wear and tear and if somehow this wear and tear can be stopped, or better, reversed, we can remain young forever. This doesnt mean all illnesses and accidents are ruled out (if possible, why not?), but if somehow this process of wear and tear is halted, a big problem is solved.
I feel scientists should consider multiple possibilities. What about changing bodies if ageing cannot, for the time being, be stopped. Stem cell research shows that we can grow body parts. We can grow our bodies, and then get our brains transferred to the newer body when we want to.
If somehow our self learns to live and function without a body even then we can become ageless. Why bind the soul, the real existence, to the vortex of biology?