i won a giveaway and the person wants me to download skype to send me the files

i won a giveaway (Call of Duty: Modern Warfare 2 DLC Packs) and the person wants me to download skype to send me the files, i thought i would be receiving a gift or cd key, and im not comfortable download files from some random person, as i could be downloading a virus or keylogger or anything

is this legit? please help me, as this is my 1st win (typical of my luck for this to not be legit), and i dont know what i should do, downloading files does not seem like a safe or viable option, he could just take the game back with the original key?
please help

after looking at the person's steam profile, it seems he doesnt even have modern warfare 2, this seems very suspicious, and after looking at his steamgifts profile things look even more suspicious, and i feel i wont be accepting,
i mean what would happen after he has sent me said files, and one day i have to reformat my computer, clearly i would not have this prize anymore

i was unsure about bringing this to the forums, but the guy is pestering me to reply and i have not heard from support yet and just wanted to know what the community think on the subject