I think its a really tough choice.
Plumbing is huge. Its reason #1 in my book why the "health care has gone to hell in a handbasket" people miss the boat. Its not sexy, but the progress in "sanitation" are profoundly more important than just about any other technologies IMO.
Another big, and usually omitted from people's calculation, are the changes in chemicals that 1900-1950 brought (petrochemicals, CFCs and HFCs -- can you say freon, refrigeration, air conditioning). Of course saying how good those were gets us in all sorts of trouble with all sorts of people.
And, especially if you fudge a few years into the 50s, most of the space travel stuff was done in the earlier period. (Don't get me going on how we screwed up space development in the second half of the 20th.)
On the other hand, of course could not be having this conversation without the Internet. And as someone who has felt first hand the constraints of small town America -- which still lived in that pre-1950 world for my childhood. I'm not sure I would have escaped even as much as I did.
On balance, I probably agree with you, zombie, in terms of 1950-2000 vs. 1900-1950. But not about 2000-2050. I'd much rather be 22 now than 52. Because I think the only time that offered as much potential for world-changing-for-the-better as today does was the world on the brink of the Industrial Revolution. And this one starts from a position of much greater wealth.
It might not happen in the USA, alas. And I would be extraordinarily surprised if it happens in Iowa. The Industrial Revolution didn't happen in Spain or Portugal or Venice. But I think its going to happen.
I'm just going to be too geriatric or dead to enjoy it.
And do not be conformed to this world, but be transformed by the renewing of your mind, that you may prove what is that good and acceptable and perfect will of God.
Romans 12:2 (NKJV)