8) Be willing to relearn what you think you already know.
This is definitely a sticking point with most people trying to make the transition over to Ubuntu. These individuals cling so tightly to doing things on a PC as they always have that any deviation amounts to personal anarchy.
Its important to remember that Ubuntu is not going to be like other operating systems. As a Linux distribution, it has laid things out in such a manner that it will undoubtedly seem foreign at first to some people. But diligence will pay off. And believe me: not only has Linux saved me big dollars over the years, learning as much as I could about the OS has even proven to be profitable to some extent.
Take the time to learn all you can as time permits your Ubuntu experience will benefit from the effort.
9) Upgrade/update when it makes sense to you.
From a security perspective, it would be irresponsible for me to sit here and tell you not to upgrade your system. After all, Ubuntu updates are there to help you with your computing experience, right?
Sure, so long as you understand that just like a Windows update gone wrong, Ubuntu updates in some cases do create problems that were not there previously.
My best advice is to setup your updates to alert you to them, then install them after ensuring that if the update goes badly, recovery is only going to take a few minutes to restore your system. The other option is not to bother with updates, while being aware that you could be putting your system in jeopardy.
The simple fix is to clearly backup and research updates before installing them. You would be surprised what a few well-placed Google searches can turn up.
10) Make the commitment.
Using any distribution of Linux, Ubuntu or otherwise, is about commitment. Most people that switch from Windows to Linux have no idea what they are in for.
I myself had a revelation a few years ago when I first tried Red Hat, and later started using Debian. In each instance, I found myself tempted to turn back. And to a lesser degree, I continued to use Windows as I learned about what made Linux tick.
Today, I like to think I am fairly comfortable with almost any distribution of Linux. I find myself quite at home troubleshooting most Ubuntu issues as they arise.
My advice to those who want to try Ubuntu is to use the Wubi installer. And for those who know that Linux is the way they want to go no matter how difficult they might perceive it to be the next day I suggest a dedicated installation with VirtualBox or VMWare providing a Windows guest installation.
While I may run four Linux boxes, I still find that having access to a Windows install is handy from time to time. Not so much for the software, but rather to serve as a reminder as to how far I have come as a computer power user.