Clean, bubbly and soapy are good adjectives. That's exactly how I would describe the 2004 transfers too. I don't think it was a good restoration because they removed too much film grain.
I much prefer the 2006 gout because that looks like an actual film transfer with grain. Not great but at least it feels authentic.
EDIT: someone mentioned 192kbps dolby surround. Isn't under 200 kbps pretty lousy? Is that low or high for most dvd releeases? What about the 2004 versions?
As for the grain, I have a theory why it's so prominent. I think the blacks were taken down in a quick adjustment to make the black bars finally be black. This would make dark grain on bright surfaces such as Hoth more apparent.