Post #4 has the link to the Microsoft page that will let you create a DVD or USB flash drive installer.
This link provides for a clean install of Windows 8 but the steps are identical to Windows 10 including the section on deleting existing partitions.
Just in case you can pull your Windows 10 key using produkey
You may need to install additional drivers but Windows 10 is has a big list of native drivers. You can go to your computer's support site and download any Windows 10 specific drivers
Edit: Because your computer has already been activated when you get to the Window asking for a product key you can simply click the I don't have a product key at the bottom of the window. Windows 10 will automatically activate when you are online.
Edit Edit: Besides your personal data don't overlook items like your browser bookmarks and any email if using a email client.
Edited by JohnC_21, 06 July 2016 - 08:43 PM.