www.imgburn.com (it's 100percent free and is much better than Nero)
set it to MODE > BUILD (and might need to change... OUTPUT > DEVICE) and then you can add files you want to burn and select write speed (8x burn speed is a safe bet for quality on almost any drive, although if your burner is new odds are you can burn faster especially if your using Verbatim discs etc)
it's best to use Verbatim media in general as it's less likely to fail vs your average stuff. but since you got Memorex media i would burn @ 8x as odds are burning @ 8x on Memorex DVD media will produce generally good results.
p.s. if you got 2 burners in your PC you might need to select which one you want to burn to in ImgBurn.