I hated The Wall the first few times I listened to it - that's an album that really has to grow on you. But it is a great piece of work.
Atom Heart Mother (the song) is too long, but it has a few "oh my god" moments, like when the orchestra really gets going near the beginning, or when it all folds in to just Rick Wright's synth and Roger's bass. I heard some story about them recording the backing track all the way through in one go....must have been tough.
I really like the title track but I do think they repeated the main theme too many times and they shouldn't have included a reprise of Breast Milky.
My favourite song on the album is Summer '68. Again, really underrated.
Yeh, the three 'meat' tracks, Summer '68, If and Fat Old Sun are VERY good. Fat Old Sun is a mainstay on my 'stoned' playlists for the occasional times I need to play it