A hard disk drive or other disk-based storage device comprises a storage disk, a read/write head configured to read data from and write data to the storage disk, and a controller configured to process data received from and supplied to the read/write head and to control positioning of the read/write head relative to the storage disk. The storage disk is partitioned into at least first and second regions, with the first region having a substantially higher average data transfer rate than the second region and being utilized to store data that is accessed more frequently than data stored in the second region. In one embodiment, the data stored in the first region is not stored in the second region or in any other region of the storage disk, and is randomly distributed across a plurality of sectors of the first region. The first region may comprise one or more outer annular zones of the storage disk and the second region may comprise one or more inner annular zones of the storage disk.