Java 1.6u10+ is required to run the application. You can get a recent version from http://www.java.com. It is recommended that you have 1 Gb of memory, but GenomeView will work with less. Similarly it is recommended to have a dual-core or better processor, but GenomeView will work with less.
The most straightforward way to start GenomeView is by Java Webstart.
Clicking the above button will immediately launch the application.
You can download the latest version from http://sourceforge.net/projects/genomeview/
Unpack the zip file to a directory and start the genomeview-
java -Xmx1g -jar genomeview-<version>.jar,
where <version> is replaced by the appropriate version number.