I cannot seem to open Minecraft.jar from the file browser. Everytime I try, I select open with, then Sun Java and nothing happens. I've tried the terminal too, but that fails and just reports a load of errors. Can somebody help me?
go to the folder with the .jar file.
java -jar filename.jar in the terminal
to see, what Java versions are installed. Often there is more than one.
to get more help, specify your prefered version with
update-java-alternatives -s VERSION_NAME
You should install java run time and you can run with micro emulator. You can consult the following post: http://callthetricks.com/3375/jar-file-ubuntu/