Can't not view burned DVD

Hello,

I have Windows 7 on my pc. I have been trying to create a dvd using Windows dvd maker. I follow the steps to add the videos that I want to burn and it says it burned the dvd, but when I reinsert the dvd into the pc to play it, it says the disc is blank. It will play in my dvd player either. I have tried several times and I am not sure what I am doing wrong. I have never burned dvd's before. My burner works because I am able to create music cd's and burn pictures and files to a disc. Can anyone tell me what I might be doing wrong?