What should I do about this boy?

Okay so today I was talking to my best friend on FB (who happens to be a boy) and just out of no where he asked me to go out with him and then told me to send my response in a message because he had to go. It's been about 5 hours now and I haven't responded mainly because I'm in complete shock. I mean I do kind of like him and I guess the main reason for me holding back is I have no idea how to tell my parents, as far as they know to me boys have cooties. So how in the easiest way possible can I tell my parents I want to have a bf... Thanks.