I disliked TPM in many ways but then years later nostalgia set in, I watched it again with a less critical eye and actually enjoyed it. I agree that it had a realness to it the other two movies don't have (which is funny to me as at the time, TPM struck me as having too much CGI...boy did Luca$ prove me wrong on that one!).
ROTS was not that bad to me and I enjoyed most of it from day one. I can still watch it here and there and enjoy it.
Now AOTC is another story entirely, I H A T E that movie and always will, and I feel that it is the least SW-like out of all three PT films. I can't sit through the entire movie and when I saw it in the theatre on opening day, I was so bored that I walked out about halfway through to stretch my legs and didn't rush to come back...that says an awful lot coming from an SW fan like me!