There are freedom issues with VirtualBox:
http://trisquel.info/en/forum/virtualbox-being-removed-trisquel
Try this from command line instead (assuming you have KVM and Qemu installed;
if not, sudo apt-get install KVM Qemu first):
This creates a flexible disk image:
qemu-img create -f qcow2 trisquel.img 100g
In the directory where you made your image put your iso and:
sudo kvm -m 1024 -cdrom trisquel_7.0_amd64.iso -boot d trisquel.img
To start the image after install do:
sudo kvm -m 1024 trisquel.img
-m is the amount of memory you want to allocate. 512 is probably enough.
Do "-soundhw all" before the path to the image if you want sound
just type "sudo kvm -m 1024 -cdrom trisquel_7.0_amd64.iso -boot d" to boot a
live CD
You could also try gnome-boxes, but the terminal is much, much easier.
HTH
