@Andar: Well in America they assume we are Idiots about computer science and take it VERY SLOOOOOWLY. Thing is that's fine of your not naturally skilled at it, but for those of us with raw talent the higher education system is a giant drag.
Yeah, I remember somebody telling me they were in a 2 semester program for CCNA certification, something I got in six weeks in an 'adult education' course meeting once a week in the evenings...
To answer the OP's questions - yes, learning Ruby will make most of what you asked rhetorical. But if you really want to learn Ruby, you need to learn how to code, and to do that, you need to forget about games for a while and just learn how programming languages work: conditional branches, loops, states (different from what the word states means in a game context), basic searching and sorting algorithms, etc...
You'll start off making simple "console" programs (the ones that work in that big black "cmd" box), and slowly work up to creating a graphical interface, and then a GUI. (you'll make a console UI first).
It's not an easy process, but if you stick with it, you can get the basics down fairly quickly (within six months if you put in some time in the morning/evenings, less if you can put in more time). I've never been much for the video tutorials for computer science, preferring dead-tree books (or online books) which let me flip back and forth and reference things as I go. Personally, I don't think video is really a good medium for conveying this information - but other people seem to do well with it: different learning styles, I guess.
In an ideal world where time wasn't an issue I'd say learn C, then C++, then Ruby. But since time is an issue, if all you really want to learn to code for is RPG Maker, jump right into Ruby. Ruby is a VERY object oriented language, so you'll have to wrap your head around that concept in order to really make any headway. Just a heads up on that.
Learn how Enumerators work. That's a pretty important 'feature' of Ruby. Understand hashes, and how parameters get passed around, including the 'splat' operator. Beyond that, you can get by with the stuff most programming languages have. If you want to work with other people's scripts you must learn how aliasing works - another important Ruby feature. If you're coding your own stuff from scratch you may or may not need aliasing (it becomes a design choice, so you should know enough to make that choice intelligently).
If you think you may want to work with another game engine down the line (like if you want to work with 3D at some point), it's definitely worth the time spent learning the 'scripting' here first. All the algorithms and logic (other than a few Ruby-specific features) will carry over, so you'll have an easier learning curve wherever you go to next.