Glad you made it through the installation.
Well, if you forgot the root password, you might try to boot in single-user mode.
1. Reboot your system
2. When beeing asking to choose F1, F2 and so on, you'll see a lone hyphen ('-').
3. When you see the lone hyphen, stop the boot process by typing '-s'.
4. It'll ask you to hit enter, do so.
5. It'll ask you about the path of your shell, type /bin/sh or simply hit enter, twice.
run the following commands:
Now simply run 'passwd', and choose a root password.