There is information on both those options in the Blue Prism product help (in v5 press the ? symbol in the menu bar). Both these options are for Browser/IE applications, and the selection on these options will depend upon if the browser application you are interfacing with uses the Java Runtime Engine or HTC components. There is also a small section in the Browser Automation Guide about the Java option.
My recommendation would be to leave these options at their default value and experiment with them if you know otherwise (i.e. you know your app uses JRE) or want to experiment because the browser interface is not working.
