I installed another distro to second drive, and later removed it. Now when I boot, I get grub prompt with 30 sec choosing time. It didn't happen with fresh elementary install, bootloader didn't even flash, it went straight to elementary. I want that back, how?
To not see the GRUB menu while booting:
Open terminal and run:
sudo nano /etc/default/grub
GRUB_TIMEOUT value to
0 which is 10 by default.
If then you need to change to Recovery mode in some instance just press
ESC when elementary starts. Then the GRUB menu will appear giving you the change to select the recovery mode.
If you are using any Ubuntu based distribution, then it should support PPAs. You could install "grub-customiser". A Google search would help you out.
Other way round is modifying the configuration files. This is explained well on this page. I would not like to copy it as it is well written.
Grub-customiser would be easier to do the task.