If everything has gone smoothly, you will see the main ImageJ window.

The main ImageJ window shown right after the first execution. Notice both the ImageJ version and the Java version on the status line at the bottom.

The status line shows that we are running ImageJ 1.46r using Java 1.7.0 update 10 in a 64-bit system. Everything is ready for you to start processing images, but there are a couple of aspects that can be improved.