See also:
viewtopic.php?f=6&t=2601Your layout looks a bit messy but I think part of your problem may be that you might have installed the boot manager (grub) onto the 2nd drive
/dev/sdb rather than the first
/dev/sda and that is why you having a problem booting!.
When installing, always use /dev/sda for the bootloader!.Your other problem is simply that you
don't have enough room for anything Zorin as you have barely enough space!.
A normal Linux lpartition layout should have 3 partitions.
swap (double the size of your RAM but no larger than 4GB)
root partition of about 15 to 20 GB
home partition of a minimal 20GB >>>>>>>> plus
Please look at the guide link I posted and the screenshot of my layout and get back with any questions.