This is where i ended up getting to
Root - drop to root shell prompt
Cant navigate. Arrow keys arent working...
Ok, we need to solve the USB boot issue, then,
I recommend downloading the Zorin ISO fresh, then wiping and burning it to USB fresh.
Ok...let me see if i can manage that on this other machine
Little confused by this... not sure which is the flash drive here as i plan to clear and format it ready to reflash
If this is the same you used to install Zorin OS with, it looks like it is the last option listed: SM_USB20 Zorin OS 17.1
Sorry forgot to mention: i don't have any other flash drive inserted...In fact this usb is the only external device connected which doesnt appear to be what is shown here
The USB drive is coming up as a two separate drives.... i'm a little confused as i'm not sure which to format and flash?
It looks to me like the one marked as Zorin 17.1
You can check the size of the drive as an indicator as well.
Seems that the drive is being read divided as two separate drives....why is every step throwing up another problem every time! 
Why not wipe that USB drive and format it as exFAT, then burn the Zorin .iso to it?
Thats what ive tried to do...but how do you wipe a drive and burn onto it when its being presented as two.... divided they are both 3.5gb...Zorin needs a minimum of 4gb.
You can use Gparted if you are using Zorin OS on the other computer you are using now. If it is Windows, you can use Windows Partition manager.
I am not sur I remember how to use the Windows partition manager.
But in Gparted, just click on both of the partitions of the drive and then click (-) icon.
They will show as freespace.
Right Click on one of them, then select Resize
Then slide the size of the partition into the free space freed by removing the other partition to reclaim that space.
Right click the new large partition and select Format.
Choose exFAT as the format option.
Ok, yes other machine is Zorin too. its showing as a single drive in gparted already fortunately. There's no "ex-fat" option? Its greyed out.
FAT32 will work. It has a max size cap of 4 gigs per file, which is why I defer to exFAT is all.
GPT is fine.