While you can uninstall GRUB, that would mean you have to set up another bootloader and is probably not worth it. There is no reason to use another one since you just want the GRUB screen to be hidden. I believe that all of the other bootloaders work in similar ways, so you shouldn't worry about installing something else.
If what you want to do is hide GRUB. This is possible, and quite easy. Press Alt+F2 and paste this before hitting Enter:
gksudo gedit /etc/default/grub.
A text-editor window will open, showing something like:
GRUB_DISTRIBUTOR=”`lsb_release -i -s 2> /dev/null || echo Debian`”
Remove the two
GRUB_HIDDEN_TIMEOUT_QUIET. Save the file, open a terminal and run
sudo update-grub. Reboot and you should have no GRUB window show up.
1 to avoid potential problems. GRUB will flash by, but it won't sit there for 10 seconds.
If you want, you can do this graphically.
Run these commands in a terminal window:
sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer
Once that's done, search for and open GRUB Customizer.
Go to the General tab and deselect
show menu and
look for other operating systems. Click the refresh button (blue circular arrow near the top right) and then click save.
(NOTE: GRUB Customizer does not seem to support EFI/GPT based systems.)
Reboot and see no bootloader.