This can be done through Events, not only is it easier, it is smarter to do as well.
Stop wasting the time of many a person by not only having them look at this pointless thread, but also waste their time thinking about how to deliver the bad news to you that it is a pointless thread without seeming like they are flaming you.
Using the event commands Show Picture, and Screen Tint (to black), and Message Dialogue, you can easily accomplish what you are talking about.
If you are this unfamiliar with the powers of Events, you may consider reading some tutorials and familiarizing yourself with RPG Maker as Events are the most commonly used feature of the software to produce your games.
Lastly, Scripting should only be used to create a feature if it is impossible to accomplish with scripting, or otherwise a better choice. Many people on this forum have created wonderful games without even an inkling of scripting. If you are unfamiliar with scripting, it should be a last-ditch effort and otherwise in the back of your mind until you have reached a point where you can't do what you are attempting to do by conventional means.