I've enjoyed the Plato Dialogues I've read - I thought they were very clever.
Thomas More's 'Utopia' is another good read.
I'm mainly drawn to writings on the moral philosophy around animal rights (e.g. Peter Singer, Mary Midgeley) which is an area that interests me. Descartes seems to have been an idiot as far as I can make out - he thought cats were machines.
Although I have also read the first couple of sentences of Wittgenstein's 'Tractus' a few times - "The world is all that is the case."
Betrand Russell's 'History of Western Philosophy' is a fabulous book.
I think a lot of Buddhist writings are at least as profound as a lot of the western philosophy I've encountered.