How do I burn 7 GB file onto two DVD's?

I have downloaded Grand Theft Auto 4 on PC and it has been saved as image files. The two files together are 13.8 GB, but thankfully split into disk 1 and disk 2. But, obviously, these are also too large to put onto my DVD-RW disks. Please can someone help me by giving me short, simple and easy tips on how to burn these files? Any help would be much appreciated :)