A useful guide

Hello.Which is best DVD-R or DVD+R - I have been using Fuji DVD +R media and have had no problems with any disc. Any movie that I have backed up seems to be very good quality. yesterday I went to Best Buy and the guy in the computer dept told me DVD-R is best for videoWhich is best to back up DVD movies ?? I hope it's DVD+R cause I have already done a lot of them on that media