I`v bought a second 2tb internal ssd drive for the laptop so I can make backups of the block data every now and again (perhaps monthly).
Why? Thousands of other people have a backup, if your disk fails, that's the part you can quickly reacquire. Your system benefits more from more RAM.
From what I can tell I need to copy the folders 'Blocks' and also 'Chainstate'
I'd just copy the entire
.bitcoin directory, including those 2 indeed. But you'll need to turn off Bitcoin Core each time before copying, so you don't copy incomplete files.
I'd use
rsync for this, it's much faster to update your backup than copying everything again.
also, on linux (specificaly ubuntu) can I just copy / paste these files onto the new drive and the next time I do it, will it just copy the new stuff that`s been added or will it be awkward?
On windows it gives the option to 'Skip' files that already exist.
You can't skip files if they've changed. That's why
rsync comes in handy: it only updates the updated files.