Is it possible to run a script in the editor so it doesnt have to run it again the runtime????

Basicly the answer is in the title >…<

If you’re talking about making an editor script run without having to press Play, then you want to take a look at the following:

http://unity3d.com/support/documentation/ScriptReference/ExecuteInEditMode.html

Yes, pretty much the entire editor / inspector system is written in scripts like this. See here http://unity3d.com/support/documentation/Components/gui-ExtendingEditor.html for some examples.