I spent hours trying the 5 minute install and kept getting errors that it could not connect to the database. I ran through all of the forum tutorials, yada yada. I gave up and tried another blog software that gave me a testing wizard to test connection to the database. The wizard stated "cannot use on Windows servers" and I got the same database error as I got from WordPress. So I changed my hosting account from Windows to Linux and lo' and behold WordPress now works fine.
So - if you are having problems with WordPress recognizing the database, check to make sure you are running on a Linux server.