No, the 3gp videos will not play on a dvd player. You can convert them to dvd video using DVDFlick, which is a free program found here: http://www.dvdflick.net/
DVDFlick can be set up to burn to a disk automatically when it is finished with the conversion. If you want to do this, start DVDFlick and look at Project Settings. Then click on Burning and put a check mark in the box that says [I]Burn project to disc[/I]. Make a label there, be sure your dvd burner is recognized by the program in the next line, and then set burning speed (I suggest 8x).