Some servers force you to do it in the .htaccess and others force you to do it in php.ini.
The determining factor is whether php is ran as an Apache process or not. Also it depends on whether allow_overide is on or off in the master config file.
Looking at some of the things you want to change I doubt very seriously you are going to be sucessful.
The syntax for the .htaccess file is:
Edit: I was unable to do some of what you want to do on a shared sever on my local machine where I could write to the master file. There are some hard limits that you can not overcome.