Missed the question about case and quotations. It's always best to assume case matters, even if it doesn't. Keywords (SELECT, DROP, etc) in SQL normally aren't case sensitive, but the minute you start thinking the same applies everywhere else (read: scripting, most places on linux) is when you get into trouble.
As far as quotes vs backticks, here are some answers:
https://stackoverflow.com/questions/...ticks-in-mysql