Ok where to start. Hmm, well, er. I thought I had read SF works till I could read and learn no more. Yes I know, I do feel a prat, and will never make this assumption again. Ever.
I have been moved to tears, by books such as "Enders' Game" and "Speaker For The Dead", and gasped in awe at Alistair Reynolds "Revelation Space" books.
However this has to be added to "Speaker For The Dead" and Philip Pullmans "Dark Materials" trilogy as life changing reads.
You may well read "Childhood's End", and as i did for 30 minutes, stand outside, I finished it about 01:30 one saturday morning, and i cried my heart out. Does it have a happy ending, does it make you sad. Maybe, but it will, i hope, make you feel special.
If you read nothing else this, I say read this.