"the universe is expanding"

Any astrophysicists in the crowd here? I mean any who have a little experience with which to leaven their academic laurels? I'm looking for someone who is not afraid to not-know.

Here's the situation: Today I wrote a letter to a friend, the widow of a pretty well-known scientist. And I asked her if she knew or knew someone who might take a swing at my question. She wrote back kindly enough, but conceded that it lay outside her fershur boundaries. So, if anyone else wants to take a swing and keep in mind my inability to do science ... I'd be interested:

Here is what I originally wrote:

Yesterday, driving to the supermarket, I was idly listening to the radio and there was some sort of discussion about relativity or the universe or something space-oriented going on. What caught my ear/mind (if I heard it correctly) was the premise that "the universe is expanding." But whoever was discussing the topic explained that an expanding universe didn't just mean that all those heavenly bodies were inhabiting an ever-expanding stage. It meant that both the space within which those heavenly bodies lived and the bodies themselves were expanding. Everything was expanding all at once.

If this is anywhere near to an accurate rendering of what was being discussed, then it became a delicious mind-bender. 1. If everything is expanding all the time, then the notion of "expansion" is left flopping helpless as a fish on a pier: expansion has no meaning without a point against which to measure its expansion. I don't mind a bit that facts should outstrip language. I don't require a religion to explain it all -- not even the religion of the intellect. But it does make me curious: 2. If my rendering is anywhere close to the truth, then what value (from a scientist's point of view) does such a theorem have? What does anyone know once they know that "the universe is expanding?" From my ignorant standpoint, it sounds a little like saying a dandelion is a dandelion or blue sky is blue ... self-serving, perhaps, but not really informative. Does "the universe is expanding" have some use or is it merely better than some Spanish Inquisition point of view?

Obviously I am missing something here, but I figure that those who have made science their task -- and perhaps got pretty good at it -- can explain in ways that leave aside the fluff.