the only thing what is important is when changing from host is that you can use php and sql database ( ofcourse update versions)
If so than back-up the current forum.
You can on the new host install a new forum so you know that the settings are good.
At last you can restore the database and overwrite the current database from the forum.
It's very easy to do.
If you are searching for a good and cheep host with a lot of features, take a look at
www.westhost.com.
You can chose there the version of php and more.