Sound works well on virtual box. You'll have to use a usb speaker if booting from a usb flash. There is currently no sound driver support.
My Suzuki booting off a flash drive. Remastered Ubuntu 10.04. The original won't get you past the monitor screen (it will only show a blank screen). My 3.5 GB is fully installable and has some applications pre-installed. Post a comment so I can send you a link.
I've uploaded my Remastered Ubuntu 10.04 for Laptops with nVdia. Feel free to try it. This is part 1
If you're fond of dual booting your computer, there are two ways to restore the master boot record on vista.
A multiboot cd created from SARDU which can be used to boot linux. It can even be used to install Windows. Force your old pc to boot on a usb using PLOP or clone a hd. Plus a lot more!
Using disk utility makes a .cdr format image. This tutorial shows how to convert the image to ISO using hdiutil.
Everything works fine even the sound. If you're looking for a Linux substitute for windows. Ubuntu is great for newbies.
Managed to boot my Remastered Ubuntu 10.04 on a new Macbook using a 16GB usb flash.
Here's part 2 of my ISO.