From best to worst:
1. BB2. I still have fond memories of that show. Everything fitted together perfectly. The housemates sometimes disagreed but for the most part all got on, but still managed to entertain. The house was great, the mix of housemates even greater, and the production was absolutely superb. Best BB, by far
2. BB3. I agree with another poster on here that I didn't think BB3 would work - but it ended up being great. There was a lot to keep you entertained and the divide was a classic BB twist. It has a lot of memorable moments that stick in your head as well. Only reason its not top is because the housemates had become too media savvy and WERE playing up to the cameras. Oh, and Jade.
3. BB5. Probably had the biggest number of "goings on" in a BB. There was always something to talk about. The characters were the best mix since BB2 and were engineered to create big conflict, which definitely happened. My main criticism is that the production was terrible (it has been going downhill since BB2) - 29 minutes of the Friday show were re-caps, the housemates heard about the bedsit, and the eviction shows were major anti-climaxes. These were the sorts of things that just wouldn't have happened in BB2. The show ran out of steam after fight night as well, with producers effectively delaying any major advancement in the show for two weeks after the brawl. Picked up towards the end, though.
4. BB1. Very clever show, no gimmicks, worked very well. Of course, Nasty Nick made it, but the media innocence of the housemates was refreshingly good. Production was superb. The whole show felt "fresh." Probably scores low because, no matter what you thought of it, big house events only cropped up about once a week... we were all glued to it because we couldn't see how entertaining Big Brother could be. If this show was run as BB6, everyone would call it boring.
5. Celeb BB3. I don't like the celebrity versions as much as the main show, but this one worked quite well for a celebrity series. There was no real "special treatment" of the housemates, and a couple of pretty good twists. The celebrities themselves were good sports and all had different personalities, as well. Once again, production was bad, but bearable.
6. Celeb BB1. It was OK. Jack Dee made it, of course, and some of the characters, like mad Vanessa Feltz, were quite entertaining. Good production, too. Not much happened though - it was quite a dull celebrity series, really. And we voted off Chris Eubank first, which was probably a shame.
7. Celeb BB2. A really dull celeb BB. Not many redeeming features at all. The only one half-bearable was Goldie, and he got chucked out first. Mark Owen is the second worst winner of a BB ever. None of the housemates let their guards down and were given very little to do by Big Brother, which left them sitting around murmering to each other and making quilts. Still, not the worst BB.....
8. BB4. Now, I'm one of these people who thinks BB4 could have worked if it hadn't have been for some unlucky nominations and poor public decisions. However, even if housemates like Anouska and Fed had been kept instead of say, Steph and Scott, it still wouldn't have compared to previous BBs. Cameron is the worst winner of Big Brother ever, and it was obvious halfway through that the producers got more and more desperate when they realised it was a flop, and tried to throw twist after twist in to spice the house up, only for all of them to fall flat on their faces. Dull housemates who wouldn't let their guards down - there were some real b*tches in there, but they never let the public see that side of them. Gos is probably the biggest waste of space in a Big Brother house ever. And the producers got more and more manipulative in this show - it was obvious they edited Cameron to be the winner, and since then they've been keen to carry on this audience manipulation. Shame.