[Ti] 'double' DVD on an Al-book ?

[Dr. Trevor J. Hutley]

I needed to archive some of my older files on to DVD (DVD-R).

I saw in the store some double-layer DVD-R, holding 8.5Gb, compared 
to the regular DVD disks holding 4.7 Gb.

BUT the pack said that only a PC could burn double layer disks, a Mac 
OS can only burn single-layer.

So I bought a pack of regular 4.7 Gb DVD-R and came home puzzled.

Is this higher capacity disk limitation really due to the Mac operating system?

Is there no way I can use this kind of higher-capacity DVD for storage?

Is the DVD-R UJ 816 in my Al-book the limitation?

Can anyone shed some light on the situation?

regards,  Trevor