So I just got a computer from work for free but it's a rather old iMac, probably from 2006, and it has Ubuntu on it. I have no clue how to use this software and the previous owner is unknown so I can't get his password for it. I have been trying to reset the password for the admin so I can uninstall the software but I can't reach the grub menu. When I went to check the settings for the grub menu on the guest user profile, there was no file for it under etc/default/grub and I cat find any file about it anywhere. It is currently running 12.04 and I can't figure out how to reset anything. Please help, all I want is to know how to enter the recovery console without the grub menu or any other faster way to uninstall the software. Thanks.
Depending on the configuration, you may be able to force the GRUB menu to show up by holding Shift when it is running. (To be safe, hold shift before you start the computer until the menu shows up or Ubuntu boots.)
If Ubuntu boots without showing the GRUB menu then this didn't work.
If that doesn't work, pressing Esc may work.