copyright != license
They are two separate concepts, and each affect creations in separate ways.
I used the site tags so you can click-through for additional research.
Copyright is a legal concept, ... that grants the creator of an original work exclusive rights to its use and distribution
an authorization (by the licensor) to use the licensed material (by the licensee).
And the phrase "All rights reserved, ..." is an assertion of copyright over a particular creation. In other words, when you place the term "All rights reserved, 2014 Kernonnes" then you are stating that a) you created the work, b) you are claiming your full rights under copyright law (generally the Berne convention applies), and c) you are not releasing your rights to the creation.
So to sum it up I want to use a license to stop others from selling and distributing my themes, while at the same time letting others use the code if they want to.
You're not clear in how you intend to allow others to access your code so I'll cover a range of options.
You are correct in that you need some sort of license to permit some amount of distributing and using your code.
Here are some options:
- You want to give away your code, and you don't care what others do with it.
You can pick from a wide range of free, open-source software licenses. But I'll skip over the rest of this area since you specifically said you don't want end users doing some things with your code.
- You want to give away your code, but you don't want others to give it away
You're going to need a more specific open-source license than the more popular OSS licenses. OSI (linked above) provides a good overview of the various licenses that are available.
You do not want to write your own license. Don't even bother considering it - it's a rabbit hole that will lead you to much frustration and a likely unenforceable license.
- You want to give away your code, and you want to sell your code, and you don't want others giving it away.
In this case, you need to consider dual licensing. It's possible one of the open-source licenses will assist you in this effort, but they may not. You'll need to do a lot more research before you head down this route.