I myself am an agnostic atheist, in that I don't believe there can be proof of God's existence or nonexistence (agnostic), but I also don't believe there is one, despite the fact that I can't know for sure (atheist). (For those confused by this line of reasoning, check this out.)

At the same time, I don't look at it as "respecting" or "disrespecting" another person's beliefs - I simply don't care. You believe in God? Cool. That does not change my opinion of you as a person one iota. Same goes for if you don't.

I only have a problem if someone tries to "convert" me - then I lose a bit of respect for them. I'll never try to "convert" someone to atheism - if their religion gives them comfort in their lives, why should I deprive them of that? No one converted me to atheism, I sussed it out on my own.

Last year, an acquaintance of mine asked me to go to church with him. I politely refused, and told him I wasn't religious. He asked me if I believed in God, and I said no. He then proceeded to quote scripture at me and repeatedly told me I'd burn in hell if I didn't accept Jesus Christ as my personal lord and savior right then. I asked him how he'd feel if I tried to convince him there wasn't a God, and he became incredibly offended, gathered together all of his shit, and left.

I've seen him once since then. He glared at me the entire time and said nothing. It's a shame, really - he was a nice guy.