Question: I'd like to change the OS on my laptop. I currently use Windows 7, but would like to install Ubuntu, but I'm not sure exactly what I need on the new OS. I've deployed an app to Heroku, which required my ssh key, is that all I need to copy over? Or are there other files I need as well?

Answer: 
It's hard to say because I don't know what else is on your computer.
If you're afraid you might miss something, try using a tool called [Disk2Vhd](http://technet.microsoft.com/en-us/sysinternals/ee656415.aspx) to make a snapshot of your Windows 7 machine. After you have Ubuntu installed and you realize you're missing something, install [VirtualBox](http://www.virtualbox.org/) and you can run a virtual instance of your machine and go back to get the files you need. (you'll want to check to make sure your CPU supports virtualization first for any of this to work)
Is there enough space for you to shrink your Windows partition ([gparted](http://gparted.sourceforge.net/) can do this), then install Ubuntu on the freed up space? Then you could dual-boot and have both, and not be losing all of your existing documents and everything.