By DOMINGO RAMIREZ JR. Ronald Davis Jr. saw two disabled vehicles on North Stemmons Freeway in Dallas early Sunday and stopped to help them.Davis got down on a knee to check one vehicle and then stood up, his common-law wife said Monday.That's when a sports utility vehicle hit the 30-year-old Denton man from behind and tossed him over a median and into other lanes of traffic where he got hit several times."I just wanted to jump over the median and hold him," Jessica Brock Davis said Monday morning.