I wouldn't say there is THAT big of a difference.
Perhaps the difference between riding a bicycle and driving a motorcycle. You may not have the "object" programming knowledge from mIRC scripting, but you already know how loops work, how variables work (to a point), how to handle incoming and outgoing data, etc. The syntax will be different, and things will be more complex, but I still say that if you can use mIRC scripting or any other scripting that is programming-based (not something like HTML, which I suppose *could* be considered scripting or programming), then you can learn any programming language if you try.
Back when I learned Pascal and Orca/C and C++, my knowledge from programming in BASIC was very helpful in understanding how the other programming languages worked. I knew what I wanted when I started, because I knew how to do it in BASIC. So, I just needed to find/learn the correct syntax to accomplish it in the other languages. It wasn't that big of a step. Of course, then you do need to start learning the more advanced parts of the other languages that don't directly follow the "lower" language. But, once you are that far, you can accomplish the rest as well.
