World of warcraft question?

IF i could manage to get the CD keys for the BC and CATA and MOP, do i still need the discs for the hardware upgrade ? or i can upgrade it from the launcher i downloaded when first played starter edition, because i have a relative in the US who bought them for me and sent me the CD keys. can i upgrade the 22 Gigabyte of WoW i installed using the standard launcher i downloaded from battle.net to MOP ??