upgrade - Should I edit sources.list*?

I've recently updated to Ubuntu 14.04, which is also when I started using the nvidia 331 proprietary driver. When installing updates, I would get prompted with the 'Not all updates can be installed' message. Because I didn't know whether it shows up because of the distribution upgrade or the nvidia driver, I search around for a bit.

I found a potential solution using:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade

However, I also learned about /etc/apt/sources.list. I had a look inside mines and
found mostly saucy and raring sources inside sources.list.distUpgrade, and one non-trusty source inside the main main sources.list:

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
deb http://archive.canonical.com/ubuntu raring partner
# deb-src http://archive.canonical.com/ubuntu raring partner

So my questions are:

1. What is the purpose of sources.list.save and sources.list.distUpgrade? Should I remove/modify them?


2. Should I remove the raring source in sources.list?

Thank you in advance!

sources.list.save and sources.list.distUpgrade were created by the Upgrade Manager and refer to the entries before the upgrade. Files not ending in .list aren't read in and are there for backup purposes, so you can safely delete *.list.save and *.list.distUpgrade.

Regarding the raring entries, I would change them to trusty, although this should have automatically happened when you upgraded from Raring to Saucy.