Hi 
This page might help
https://help.ubuntu.com/community/Grub2/Installing
Section 2 on how to reinstall grub2. SuperGrub might make it easier in
some ways because it's more point&click gui.
If it doesn't, or if you don't want to burn a LiveCd that only has 1
function and that being to cover a fairly rare problem then the wiki might
be handy. Of course you can try either one first and then try the other =
the order you try these different solutions shouldn't really matter.
Chances are that you have been using Grub2 rather than Grub-legacy. There
used to be an issue between earlier versions of grub2 but those have been
smoothed out for the last several years. The *buntus (Ubuntu, Kubuntu,
Xubuntu, Lubuntu) have been using it since before 10.04 (released in 2010,
April (hence the version numbers)). The 13.10 was released in 2013,
October and was definitely using Grub2 unless painstaking work was done to
do something really odd.
Win8 and some Win7 machines use UEFI to boot-up but you probably don't need
to know anything about that for the case you are coping with.
http://www.rodsbooks.com/linux-uefi/
UEFI is MS's (apparently horribly broken) attempt at "secure boot", in
which case these links might help learn about that a bit;
https://www.happyassassin.net/2014/01/25/uefi-boot-how-does-that-actually-work-then/
Regards from
Tom 