1. http://www.jazz2online.com/jj2plus/p...gelscript.html
2. Any text editor. You're going to have to write scripting code, there's no way around that. If you use Notepad++ there is a syntax highlighting module you can use.
3. There is no part of JJ2+'s AngelScript support specifically aimed at making cutscenes. You're probably best off reading the readme, seeing how other scripts do things (e.g. take a look at the RabbitCity scripts) and then ask specific questions in this thread.