What is the most rational way to allocate memory?

Question

Hard disks

There are 2 HDDs - 500 and 250 GB and an external 1 TB. There will be 2 operating systems - Ubuntu and Windows 7 (and some space is left for experiments with other operating systems). How best to use hard drives:
1) Windows on one, Ubuntu on the second, external for heavy files and backups.
2) Drive C Windows and / root Ubuntu on one, drive D and / home combined on the other, external for heavy files and backups.
3) Both OS on one, the second for backups, on external file storage and backups of backups.
4) Another option?

Answer 1

I would put windows on 500, ubuntu on 250, and external for backups. For experiments, you can bite off both the first and the second disk, depending on the space taken.

Answer 2

HDD for the system is not good, even with powerful hardware it will slow down It is
up to you to share the memory, you will use it and not me or someone else
Such questions do not have a universal solution, they are individual
Ask yourself why do I need Windows, and then what is ubuntu for