There has always been 9 parts of the story out there. Lucas's original idea was too big for a single movie so he broke it down into three sets of three and did the middle one (StarWars probably beeing the easiest and cheapest to pull off, he has stated he didn't do the old Republic ones due to technology restrictions at the time). If Lucas does it then it will most likely follow this original outline from the 70's he had. I'm pretty sure this is why for over a decade he clamped down pretty tight on letting people write books (there was a old Han Solo series of books at one time, then nothing but the comic after that for years). It wasn't till he decided he wasn't going to do the last three that he started letting all these novels be written. The novels mean nothing to Lucas but a source of revenue, I doubt if he has even read any of them. Now if he lets the rights go then it's anybodies guess (but the Zahn books would be a good bet). The biggest problem will be getting Harrison Ford to do it, he doesn't work cheap, not to mention he's really getting old (62 in July), this series wouldn't even start production till after the next movie is out in 2005. Would he want to devote 6 to 8 years of his life to another Star Wars trilogy?
As far as Harrison Ford not liking Han Solo, he was burnt out on him and was really pushing him to die in Jedi (well everybody looked burnt out in Jedi, exept Carrie Fisher who was drugged out). I don't think he hated the character, I just think he didn't want to play that character anymore.