It appears that for some reason my computer thinks that .jar files are opened by explorer.exe. I am using windows seven and it will not allow me to change that program that opens it by default as a .jar file is a program and you cannot open programs with other programs.
A .jar file is not a program, it's a Java Archive file. It's a zip file (IIRC you can change it to .zip and extract it with Windows Explorer but I haven't tried it) containing Java bytecode files, resource files and metadata. The JVM extracts the files inside and then uses those to run the Java code.