Ye' old general discussion board. Basically, for everything that isn't covered elsewhere. Come here to shoot the breeze, shoot your mouth off, or whatever suits your fancy. This forum is not for asking programming related questions.
It depends whether they leave register_globals off or turn it on for you - if they turn it on you shouldn't have any problems. Of course you really should start converting your scripts to not having to rely on register_globals...
Ask your host to turn register_globals on when they upgrade - most hosts will because the change will affect a lot of people, then you'll have some breathing space in which to upgrade.