I recommend Python. Ignition scripting uses Jython, which is a Java implementation of Python. This means that you have access to the Java libraries on top of the 'standard Python' ones.
Python is one of the easiest programming languages to learn. Tutorials abound for python in the interwebs, so there is a lot of information ripe for plucking. 
Udemy has some nice online courses available. Be aware, most are Python 3, while Jython is at 2.7, and there are a few minor differences.
We also have this thread of Favorite Resources: