dvd burning

[delfina]

I am not a complete idiot where technology is concerned but have been having problems copying dvds. Am using Nero OEM Suite and DVDshrink. Everything seems to be ok with dvdshrink at first but when i go to burn it it tells me file is too big or goes through the motions then just stops! If i put the dvd into dvd player it tells me its wrong disc! Can anyone tell me what im doing wrong? Think i need an idiots guide to using nero and dvdshrink what do you think?