Jeffrey,
Just in case you ever have the itch to do such a thing again, I could suggest going to 114th Ave off of Tower Rd. Easy to get to, but kind of a drive. Pena to Tower Rd, north then right on 96th Ave (think there is a light there now). Follow it around and it will go north and then back to the east passing about .5 miles north of the two western north-south runways (16L/R & 34L/R). If you park on the north side of the road, the security doesn't have an issue with it, but if you park the extra 25' closer to the fence on the south side of the road, they will ask you to move. There are signs saying no parking between the runways, but unless it's changed recently, that only applies to the south side of the road. Big shoulders to pull off on also. I don't think that security and DPD will really worry about a family eating lunch and watching airplanes as long as you are not parked where you aren't supposed to be. It's been awhile since I've been out there, but the security people are really pretty nice about the whole thing even if you are parked in a bad spot. Everyone needs to stop being paranoid and living in a state of fear. If you are within the law, you have no worries. Enjoy the jet noise and listen for the wingtip vortices - pretty cool stuff.