To the best of my knowledge,
NTSC and PAL define video standards. NTSC applies to the United States, Canada and Japan. PAL is, for the most part, used everywhere else, most notably Europe (except France, which uses SECAM). If a game is labeled USA, it is definitely NTSC.
DVD-5 is the single-layer DVD standard. DVD-9 is the dual-layer DVD standard. You will most likely be using DVD-5 media (the "4.7 GB" size DVD-R) to burn your backups.
MULTI5 indicates that a game has mulitple languages, and is usually PAL. The default language is English unless noted otherwise.
You can use Swap Magic 3.6 to force games to be played in NTSC or PAL, depending on your TV standard.
Any questions related to God of War are probably already answered at http://forums.afterdawn.com/thread_view.cfm/174869.
