How do I safely partition a hard-drive to accept a GNU/Linux distribution in the presence of OneKey Recovery?

I think any way you slice it there's risk involved. Maybe your best option would be to copy this recovery partition elsewhere. Lenovo usually preinstalls an application to burn this recovery partition to DVDs. Basically, make a backup of a backup before moving partitions around. You never know what might get destroyed, or how exactly Lenovo set up their recovery partition.