Wow, that's something to hear that Season 6 was pretty bad, 'cause that's the one that sucked me in. Of course I haven't seen any of the 1st 5 seasons before that, so I'll have to catch up. I just managed to snag up the special edition of Season 1 last week at Target for $19.99, so that's a start. I did catch a Season 4 or 5 episode last week that had the previous President Palmer getting assassinated with his brother (the President I knew) in the room with him, and Jack was in hiding. And that looked pretty good, but I didn't know 1/2 the people they were showing.
I've probably seen 1/2 the episodes of Smallville from Seasons 1 through 5, and I haven't seen any of 6 or 7, so I've got catching up all around to do (damn syndication for getting me hooked on this stuff).

I personally thought that Season 2 and 3 were two of the strongest seasons so far, but my one buddy didn't think too highly of Season 6, so we'll have to see.