Don't be embarrassed, we all have had troubles getting started. No one starts as a pro - you've got t work your way there.
To log in through FTP you'll need to use the user name and password combination for the user who "owns" your website. This is likely to be the first user you set up when registering with Dreamhost. It's different from what you use to log into the panel though.
If you need a reminder, log into the Panel > Users > manage users. You should see a list of any users you have created there. If you need to you can edit the user and reset the password. (find the edit button across from the user in question).
Does that clear things up for you?
art.googlies.net - personal website