virtualbox-4.2_4.2.12-84980~Ubuntu~raring_i386.deb (63.9 MB) and
Oracle_VM_VirtualBox_Extension_Pack-4.2.12-84980.vbox-extpack (11.6 MB) from https://www.virtualbox.org/wiki/Linux_Downloads.
I installed VBox on my laptop (Dell 1545 Core2Duo T6400; 4 GB RAM) running Lubuntu 13.04 giving the guest OS (also Lubuntu 13.04) 1536 MB RAM and 8 GB fixed disk space.
Performance is okay but I'm having trouble with the screen size. The desktop doesn't occupy the full width of the screen as the image shows (red ellipses).
I can use "scale mode" but that looks ugly as though things have been stretched horizontally.
Some reading indicates that installing
Guest Addditions would help. But I can't figure out how to install it. I have /usr/share/virtualbox/VBoxGuestAdditions.iso.
I've tried to mount
But when I click on
Install Guest Additions, I see this window:
Also puzzling is that there's an option to "force unmount" when the text above says "unable to mount".