OSDev.org

If I use grub and make a disk do I need to go open source? My assumption is no because Ubuntu ships with binary blobs, but I want to be sure. I don't want to go open source right at the beginning because I may want to use some of the code in University first (when I graduate I may consider).

no you don't need to , you would only need to open source your kernel if you use some licensed code from another project depending on it's license.