As previously stated you maybe able to get waivers for for previous indiscretions; and the Air Force is very picky but make sure you talk to a recruiter and disclose EVERYTHING.

People used to tell me I had no chance of getting into the AF until I had 15 college credit because I have my GED and less than 1% of enlisted Air Force are GED holders. Give it a try the worse that can happen is they tell you no. Give it a try though dont give up just because of answers on Yahoo! if I had I wouldnt be leaving tomorrow for BMT

yes they will find out. your social security number is what they use to run the checks. you MUST disclose EVERYTHING. failing to do so will land you in a heap of trouble.. the actual charges may be waiverable. LYING ABOUT THEM IS NOT.

They are going to do a police records check every place you lived, worked or went to school. You can do one yourself and see what comes up. You will most likely be able to get into the military, but as previously stated your odds for the AF are rather slim.

Yes, they will find out. Its best to be honest with them.
You have a better chance with the Army.

Yes it is going to pull up when the do the initial background check best to be up front and honest. Depending how long ago it was etc. you might still be able to get waivers. The AF is very selective you might want to look at getting in to other branches.