Hi,
You should not create the database yourself, as moodle can do it for you. ALl you need to do is use your admin account at the start with moodle and it will create the nessecary files and database.
When asking the mysql settings page can you change you user from admin, if so you actual have done something wrong in the install process.
We took it step by step and only install mysql when it first told me to place in the mysql settings.
If you can rebuilding your server and start again and i will post a step by step guide which im writing up at this point in time here.
Cheers,