If you've taken a snapshot, you will be able to recover all your files when you restore the droplet. The snapshot is stored separately.
The "Scrub Data" option is a security precaution. What it does is over write the part of the disk that your droplet previously existed on with 0s to ensure that the next droplet will not have any way to try and reconstruct data from it.
Never destroy a droplet without making sure "scrub data" is enabled, unless you really know what you're doing. All the "scrub data" option does is makes it impossible for anyone else who creates a droplet to read your data, as droplets share the same hard drives. This has no impact on your snapshots at all.
I know this answer is late... but I still think it may as well be here.
Physically, no, but nothing other than the disk controller on the SSD will be able to access it anyway. This level of detail is abstracted away even from the hypervisor/host OS that digital ocean is using (not even disk drivers see this stuff).
This detail would still be abstracted away from the file system by the disk driver if it did actually decide what 'blocks' correspond to what locations on a cell. No one is going to see your data unless they build some custom hardware and break into digitalocean's data centers. And that is probably not going to happen.
