I will not have all your answers and my only experience comes from the many posts that I have been involved with.
Here are the requirements https://help.ubuntu.com/community/In...emRequirements
Based upon what I have learned it is very easy to install, many have requested help after a sucesssful installation. The problems encountered had nothing to do with the installation, but rather the dual boot that was required. Some uninstalling and not being able to boot windows. I think that is your biggest risk.
I have had situations where some were not able to boot Windows after installation, but that was not too common.
You would want to make a system image with the native software or to use Macrium Reflect and put the image in a safe place. In the event of any kind of problem you can fall back on the image and be ready to go
There have not been any reported problems with the partition process other than you may not be able to use the native partition software and would have to use some other software. This software has been mentioned and complimented in the past http://www.partitionwizard.com/free-...n-manager.html
Finally, wish you luck. There will be many more posters, who will give much more detailed advice. This is just the beginning, to give you something to think about.