Move Large, Frequent files closer to center of HDD
There’s not much difference between moving the files to the centre of the HD or towards the periphery. The centre you see in visual representations is just that, a rectangular visual representation of your circular. Physically, the file may be anywhere on the disk.

Deleting and rewriting the file won’t help much, as the space on your disk is already fragmented. Though I have not confirmed it, OS X defragments files below 20 MB automatically. Audio and Video files tend to be large than 20 MB, and are highly fragmented.

Assuming you are talking about defragmenting the disk, I highly recommend iDefrag. I use it every 6 months, and using the computer after the defrag is like switching from an old 56k modem to Google’s fibre optics.