Ive read you have to mess around when copying dvds if its over a certain size to make it fit on a single layer dvd. If im using blank dual layer discs can I just rip it with dvd decrypter and then burn it to a dual layer disc and thats it done?
Yes. Set the Mode to ISO Read and rip an iso file to the hard drive. Set the Mode to ISO Write, select the MDS file associated with the ripped iso file, and burn. Be sure your burner firmware is up to date, use +R DL media and booktype the media when burned to DVD-ROM.
burning at a slow speed also is smart with DL media like 2x ,heres a guide that may help too http://bbmayo.home.comcast.net/
Not all drives support booktyping. Some that do are: LG Plextor BenQ LiteOn NEC I don't think that's all of them, you'll have to check your drive to see.
Ok cheers it says I can change booktype on my NEC burner 500 times. What happens when my 500 times is up?
That's 500 total changes. Once you change the +R DL booktype to DVD-ROM, it'll stay in that mode unless changed again. It's not 500 disks booktyped but 500 changes.