Some people may not like having the boot details scrolling up their screen, however I prefer it. To disable the splash screen so that you can monitor the boot process simply do the following.
xubuntu 16.04, lubuntu16.04
Open Grub file.
$ sudo nano /etc/default/grub
Change this line.
to read as
Save and exit file.
Update grub by issuing the following command.
Next boot should show boot details rather than a splash screen.