Replying to Apple Mac Terminal code help.

So, I ballsed things up very badly.
I need a terminal code to restore all files in from the trash can...
They haven't yet been removed from the trash can. So are still sitting there. They were system files so now the computer won't turn itself on. I can obviously/hopefully restore them through the installation CD and terminal.

So, restore and not delete please.
Thanks and +karma for legit quick responses. I am desperate.

Peace