does anyone know the answer (backup)

[eduardmc]

i have spb backup 2.0, and i have installed the official sprint leak rom 3.03. i want to use a custom rom like omj which has a few pre programs installed and mayor registry tweaks. if i perform a backup on my original offical sprint leak rom, installed the OMJ rom, what will it happened to the software installed in this rom after i do a "restore"?
will all the registry from teh custom rom will be back to stock after the restore?
will all my software be installed even though i have a few program which are already installed in the custom rom?

i do want to install a custom rom but i don't want to spend countless hours installing everything that i had back to my phone.

thanx in advance