1. I don't think you need to submit anything other than the 1040X. That form has spaces for original and amended amounts. So I don't think the original 1040 is needed. (I could be wrong.)

2. Number 8 on this list suggests you should pay now.

http://www.irs.gov/uac/Newsroom/Ten-Facts-about-Amended-Tax-Returns

It sounds like you owe very little, so I'd want to take care of it now just be done with it.