I definitely feel you. I was trying to see how much it would cost to get all of the seasons on blu-ray for my boyfriend, but they definitely need to get the rest of the seasons on blu-ray. Blu-ray is just so much better.
The reason they haven't come out with season 1-5 on blu-ray is because those first 5 seasons were shot in a lower resolution hi-def. They say you wouldn't see much difference between DVD and Blu-ray for those seasons.
WTF....are you stupid....no matter what they shot them with, it is put on a dvd, which means the maximum resolution is 720x480, so they have to upgrade it to HD using an hd scaling technology(don't ask me how, but they do, how do you explain star wars in blu ray) or if they already shot it in HD they just have to place the original video on a blu ray...if it's on a dvd, there is no way you would just "not see the difference".
I think your post is a little misguided. They don't use DVD's for the source material. They go back to the original film or source to make blurays. In the case of star wars it was shot on film. Film is far superior to 1080p. Low quality film like 16mm will be grainy but anything shot on decent film will look pretty decent.
Smallville wasn't filmed on film but it was filmed in HD. Albeit the quality of the first sesaon is meh. All of smallville's seasons aired on TV in HD. They still rerun in HD and Itunes sells them in HD. Season 5 was also available on HD DVD before they went to bluray for s6.