Cant seem to create a bootable DVD HELP

Hi guys
I am already running 10.8.2 but I want to do a clean install.

I dont have a 8GB USB drive so my only option is DVD...

1. DVD R or DVD RW? Any diff? I have both.. 4.7GB

2. When I try to use disk utility to burn the InstallESD.dmg file it says there is not enough space on disk for some strange reason..only way I can do it is to use finder.. load the disk, drop and drag and click the burn icon on the left. That seems to get the file on... BUT I have tried click C on reboot.. does nothing... clicking option reboot only shows me my HD icon and no DVD option.

I must be doing something how do I make this DVD bootable?

that thing doesnt like 4.7GB disks or something....anyways...

the normal internet restore process does not work for me coz they require apple IDs to download the OS.

So after a long drawn out process I basically wiped it put snow leopard on it then upgraded it... as clean as I can get for now. I notice the Option reboot thing will recognize my SL original disks but NOT the mountain lion ones I made so theres an issue some place...I have DVD RW and DVD+R I dont have DVD-R that could be an issue.

but anyways it is done for now.. till 6 months or a year down the road when I need to re-do this again.