I rarely do upgrades and try to avoid them whenever possible, instead do always fresh installs as I like to do house-cleaning when upgrading to a new version of OS. As I have a separate /home partition, this doesn’t affect any of my settings and only takes 1-2 hours (less than one hour on a high speed Internet connection), which is comparable to the upgrade option from within 7.xx.
What is UNetbootin?
UNetbootin creates a boot option in GRUB or the Windows bootloader that will download the installation files directly over the Internet and starts the installation. I find this very attractive since I don’t have to download or burn any CD’s. It works from within Windows and Linux and a variety of distro’s can be installed this way besides Ubuntu. The process is more than ideal with the new generation of netbooks, like the Dell mini, Asus EEE just to name a few, which don’t have optical drives.