Best Way To Backup A Website?

Hey all, was told in another thread that it is a good idea to back up a website every day/week.

I'm wondering what the best way to do this is.

At the moment my site is using SQL and html files(The database is just for forums.)

So would I just need to ensure I have a current copy of my .html files on my pc, and go into my database through trap's control panel and export, or is there a better way?

I remember having a lot of issues in the past when it came to transferring forum databases from one host to another.

Also, let's say I take phpbb's database from username (rpgsearcherz_rpgsearcherz) and database name (rpgsearcherz_rpgsearcherz) and transferred over to...(trap_trap) and (trap_trap) would I need to change anything in the databases themselves, or would I just need to change phpbb's directory information to point to the new server/username/database instead of the old one?

Thanks in advance!