Quick Questions about DVDs/CDs/Blu Rays (optical discs)

Let's say my DVD has 3 files on it - 1.jpg, 2.jpg, and 3.jpg. If I want to access 1.jpg, will my DVD keep spinning over 2.jpg and 3.jpg and ignore them? Can the player only spin clockwise, and not keep spinning backwards and forwards over 1.jpg?

If I'm playing a game, and it's loading something, it's getting the data from the blu-ray/disc/HDD. Is it skipping over all of the other assets as it keeps spinning clockwise? Does it keep skipping over them and only keep the 'good' ones in RAM? Can't it just slowly spin over that area of the disc?

Is there a way to purposely spread one file's data all around the disk so that it is always being scanned, in order to minimise load times?

If one is burning to a read-only disc, it uses up all the space. Is that extra space just occupied by unecessary 0s or what?

Since my JPGs aren't using up all the space, could I write 1.jpg's contents to the disc multiple times so that it isn't wasting any spinning time? Or is that already covered by companies in point 4? Or do companies not do this?