In this step of the launcher wizard, you can configure the preferred VM that install4j will choose to invoke your application. This setting only influences the choice of the VM type after a JRE has been selected according to the search sequence. The search sequence for the JRE is specified on the Java version tab of the general settings step.
Please note that it is not an error if the selected JVM is not present for the found JRE. install4j will simply use another JVM to launch your application in that case.