My wife is applying for citizenship, and she has one ticket. This is an interesting thread. That one overly-broad question on N-400 has caused more grief than all of those other questions combined. And the IOs don't even really care about infractions (non-criminal acts).
People here seem to be divided in two camps. Those who lie by excluding moving violations, and those who lie by not including every ticket or every time they have been stopped by a cop in their entire life. Also, people here have never plead down their tickets? My wife got a ticket for running a stop sign, and got the charges reduced to a non-moving violation. So she's in-between the two camps.
I have noticed some legal advice here that's simply wrong, so I'll clarify. If you've ever been pulled over by a cop, or you have been in a friend's car when he was pulled over, you've been detained. Also if you've been in an accident and the police were called, you were detained. If a cop pulls you over and just gives you a warning, you've been detained. "Detained" is simply when a cop is talking to you and you feel you can't leave until he's finished with you. I'm sure that wouldn't affect anyone's citizenship, but in theory it needs to be reported on N-400 the way that question is worded.
Also, if your wife borrows your car and gets a parking ticket, you're the one who's been cited, not her. It's the same in most states for a red light camera (except in California). The registered owner of the car gets cited, not the driver. The good news is that if you borrowed your wife's car and got a parking ticket, you weren't cited. Also, ticket=citation, so subway hopping, jaywalking, breaking a noise ordinance, littering, etc. are all citations and in theory should all go on N-400. (Citation=ordered to appear in court)
Also, it's funny that the N-400 directions say you don't need any paperwork for fines under $500, yet some IOs ignore that and want court dispositions or DMV records. I'll try to get my wife's, but I think they've dissolved the town so I'm not sure where those records are anymore. Her DMV record won't show anything, so there's no point in bringing it. The bank doesn't even have the cashed check anymore.
Finally, there are people who checked "no" in that box and then later came to this forum and are now freaking out. N-400 states that if you KNOWINGLY lied on the form, you could be in trouble. But you didn't knowingly lie at that time, so don't panic. I would NOT bring it up. If the IO specifically asks if you've ever gotten a ticket for anything, just tell him about your tickets and say you didn't realize that you were supposed to include them since they were so minor. It sounds like it happens all the time, and they'll either ignore it or change your form for you.
Honestly, if I was an IO and someone who had lived in this country for 5 years had NO traffic tickets, I'd be suspicious.