back up 2 sides to 1 disc ?

[taffio]

can anyone help me i've got the original starship troopers dvd but the problem is half the film is on 1 side and the other half of the film is on the other side, i would like to make a backup of this film but put it onto just 1 disc !
it's a favourite film of my sons but everytime he watches it he has to turn the disc over halfway through.

and discs and kids don't go together