how do i make a backup copy of GT4 ?

[s12original]

lufcfan and Warlock thank you for your guide lines.DL-Recorder is not an option because of the cost.(about 60 euro,almost as the cost of a new original GT4).So following the tip for ripkits i did found Gran Turismo 4 DVD5 Backup Tool v1.01 at www.BackupTools.co.uk a ripkit creatad for GT4(ripkit was created by Sonix).The readme file in this ripkit contains the following lines :

Copy the entire contents of the DVD9 game to your hard drive - including
the second layer (make sure GT4L1.VOL is in the same folder as GT4.VOL).

How do i do that ??? I remind you that i've saved an image in my hard disk using Alcohol 120 and when i open the original GT4 disk with windows explorer (right clic on it and select properties) it shows total amount of data 3.09 GB but when i do the same with the image that Alcohol 120 had prodused from the original DVD i get total amound of data 5.27 GB. So how do i copy both layers in the same folder (GT4L1.VOL and GT4.VOL) ???? I will own a favor to anyone could guide me how to use this ripkit.