Hi Tony,
Welcome to the great Chordie community!!!!
We were all in your shoes when we started. How do I get this "thing" called a guitar to make pretty sounds?
It sounds like your looking in all the right places, but you won't find anything to advance your playing except for PRACTICE. If your having trouble with chord changes then that is what you need to focus on right now. Pick 2 chords like the ones from the songs you were trying out. Start slow and keep repeating the change until it rings true. Then speed up a little at a time. It doesn't come overnight, but the more time you put in, the faster you should advance.
As far as strings, steel strings are harder to learn on, but will toughen up your fingers quicker. Try changing to light or xtra light strings, these will be easier to fret as you don't have to push down as hard. I don't have any experience with nylon strings.
Remember PRACTICE, PRACTICE, PRACTICE
Keep Rockin!!!!!!!!!!!!!!!