can't install xbmc
 

i have decided to kick boxee aside since alot of my movie and tv series titles give me the prompt that it was unable to fetch movie information and i recently read that xbmc is what boxee was programmed from ut unfortunetly there was no deb package nor was it in the software repositories instead it told me to add a software source (i don't like doing this because the synaptic starts acting funny) here are the commands

and when i do the first one i get
and when i did the second one i got (it's pretty long but i started recieving errors torwards the end to i think i'll only include those)
heres the result from the next one
and after all of this xbmc was not installed i don't see it in my applications menu nor will it run when i execute the xbmc like most programs that were installed from source. i appreciate the help this could be alot better than what i am using currently

okay now it's appearing in the repositories but i am getting an error saying that it is failing to retrieve packages and of i want to resume installing the software without these packages, noting gets installed and i get and error prompt with this text

these packages also come up as "NOT AUTHENTICATED" when it's asks me to confirm the installation