Personally, I've always found other runners to be completely supportive. Even the hard-core runners will give me a thumbs up or a word of encouragement. I've never even gotten a second glance from others, unless I'm trying to dodge them or vice versa. No one cares.
I also want to say that running really isn't a graceful sport, as fantastic as some people look doing it. Everyone gets red and snotty and has to spit. DH always says I look sexy when I run... personally, I think it's the
least sexy thing I've ever done!
I say just get out there and do it. IF anyone yells at you from a car, remember that you're the one out there running and they're the one driving a block to go to the store.