"Low level format"
Also know to most techies as simply "format". There is no such thing as "high-level format". There is formatting, and there is deletion of the partition table. Microsoft's "quick format" is therefore not formatting anything. "low-level" format here would not be (more) indicative of deliberate mischief.
In any case on a machine that age, the most cost-effective wipe would surely involve physical destruction !