Well I've been having trouble getting an actual answer to this question and someone suggested giving it a shot over here, so here goes.
Will a PAL game, played through an NTSC Xbox360 that is hooked up to an NTSC tv via composite, display properly?
I think I remember having a PAL version of Outrun2006 display properly through my PS2, and offer a 50hz or 60hz mode selection on startup...I'm just assuming this was a PAL version because I don't see why an NTSC game would have such an option. I'm really hoping this works because of the recent announcement about the euro release of Dai Fukkatsu being regionless. I'd really appreciate it if someone could help me out here.
PAL/NTSC display question
PAL/NTSC display question

1CC List To miss is human; to rank control, divine.
“Fly to live and shoot ‘em all!” – Manabu Namiki
Re: PAL/NTSC display question
Typically yes - 98% of games are totally fine. Given the source material I would be very surprised if the game didn't work totally fine at 60hz. In fact it's more likely that a 50hz option won't be included...
To be 100% safe maybe contact rsg, or wait until release for confirmation.
There are some PAL games that can be awkward if you do not have specific modes set [eg. PAL of Hitman Blood Money will not run if your console SD av out option isn't set to pal 50, even if the console is running in HD and connected by vga/composite/hdmi (once the setting is set the game will actually run at any res+sync+connection)]
To be 100% safe maybe contact rsg, or wait until release for confirmation.
There are some PAL games that can be awkward if you do not have specific modes set [eg. PAL of Hitman Blood Money will not run if your console SD av out option isn't set to pal 50, even if the console is running in HD and connected by vga/composite/hdmi (once the setting is set the game will actually run at any res+sync+connection)]
Re: PAL/NTSC display question
OK cool, thanks for the answer. That was what I suspected to be the case, but I wanted some sort of verification. I'm assuming it's even more likely to work if they specifically made the game bootable in both US and EU regions.

1CC List To miss is human; to rank control, divine.
“Fly to live and shoot ‘em all!” – Manabu Namiki