Yes, that makes me very sad to hear you say that such an idea coming from a politician would be considered ludicrous by the general public, although I fear you're probably right. If we can't save future generations I would hope the least we could do is save all the knowledge we've so far accumulated.
I imagine any race capable of making the deep space journey to our solar system would likely have already worked out most of our math and science for themselves, but you never know what they might have missed, and they would still probably find all the information on our culture and history quite fascinating.
I'm not trying to turn this into an overly speculative thread either, as I imagine that's prohibited as well, but I bet the planetary scientists/enthusiasts on this forum could probably contribute their own ideas to how such a feat could be accomplished with current technology.
For instance I was reading about the life cycle of our Sun and it seems that Earth is going to spiral in to it in a few billion years when it becomes a red giant, so we'd probably have to stick this relic somewhere farther out. And if Earth becomes like Venus it probably wouldn't be a safe place to store it anyways. I imagine we would want a dead planet/natural-satellite, no plate tectonics, little atmosphere etc. Somewhere very cold and not likely to be bombarded by a lot of cosmic debris.