que é porque a fonte 64 não está atualizada, e não está pronta para get, codimension também, para cdrom, apenas desmarque cdrom na fonte de software, e lá você pode desmarcar as outras fontes até que esteja pronto para o arquivo.
Sempre que eu digito sudo apt-get update em um terminal, esses são os erros que recebo:
Ign http://se.archive.ubuntu.com saucy/main Translation-en_US
Ign http://se.archive.ubuntu.com saucy/multiverse Translation-en_US
Ign http://se.archive.ubuntu.com saucy/restricted Translation-en_US
Ign http://se.archive.ubuntu.com saucy/universe Translation-en_US
Ign http://se.archive.ubuntu.com saucy-updates/main Translation-en_US
Ign http://se.archive.ubuntu.com saucy-updates/multiverse Translation-en_US
Ign http://se.archive.ubuntu.com saucy-updates/restricted Translation-en_US
Get:11 http://security.ubuntu.com saucy-security/main i386 Packages [63,4 kB]
Ign http://se.archive.ubuntu.com saucy-updates/universe Translation-en_US
Ign http://se.archive.ubuntu.com saucy-backports/main Translation-en_US
Ign http://se.archive.ubuntu.com saucy-backports/multiverse Translation-en_US
Ign http://se.archive.ubuntu.com saucy-backports/restricted Translation-en_US
Ign http://se.archive.ubuntu.com saucy-backports/universe Translation-en_US
Get:12 http://security.ubuntu.com saucy-security/restricted i386 Packages [14 B]
Get:13 http://security.ubuntu.com saucy-security/universe i386 Packages [24,4 kB]
Get:14 http://security.ubuntu.com saucy-security/multiverse i386 Packages [1 388 B]
Err http://ppa.launchpad.net saucy/main amd64 Packages
404 Not Found
Err http://ppa.launchpad.net saucy/main i386 Packages
404 Not Found
Ign http://ppa.launchpad.net saucy/main Translation-en_US
Ign http://ppa.launchpad.net saucy/main Translation-en
Err http://ppa.launchpad.net saucy/main amd64 Packages
404 Not Found
Hit http://security.ubuntu.com saucy-security/main Translation-en
Err http://ppa.launchpad.net saucy/main i386 Packages
404 Not Found
Ign http://ppa.launchpad.net saucy/main Translation-en_US
Ign http://ppa.launchpad.net saucy/main Translation-en
Err http://ppa.launchpad.net saucy/main amd64 Packages
404 Not Found
Err http://ppa.launchpad.net saucy/main i386 Packages
404 Not Found
Ign http://ppa.launchpad.net saucy/main Translation-en_US
Hit http://security.ubuntu.com saucy-security/multiverse Translation-en
Ign http://ppa.launchpad.net saucy/main Translation-en
Hit http://security.ubuntu.com saucy-security/restricted Translation-en
Hit http://security.ubuntu.com saucy-security/universe Translation-en
Ign http://security.ubuntu.com saucy-security/main Translation-en_US
Ign http://security.ubuntu.com saucy-security/multiverse Translation-en_US
Ign http://security.ubuntu.com saucy-security/restricted Translation-en_US
Ign http://security.ubuntu.com saucy-security/universe Translation-en_US
Fetched 259 kB in 5s (48,9 kB/s)
W: Failed to fetch cdrom://Ubuntu 13.10 _Saucy Salamander_ - Release amd64 (20131016.1)/dists/saucy/main/binary-amd64/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
W: Failed to fetch cdrom://Ubuntu 13.10 _Saucy Salamander_ - Release amd64 (20131016.1)/dists/saucy/restricted/binary-amd64/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
W: Failed to fetch cdrom://Ubuntu 13.10 _Saucy Salamander_ - Release amd64 (20131016.1)/dists/saucy/main/binary-i386/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
W: Failed to fetch cdrom://Ubuntu 13.10 _Saucy Salamander_ - Release amd64 (20131016.1)/dists/saucy/restricted/binary-i386/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
W: Failed to fetch http://ppa.launchpad.net/revl/codimension/ubuntu/dists/saucy/main/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/revl/codimension/ubuntu/dists/saucy/main/binary-i386/Packages 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/upubuntu-com/tor/ubuntu/dists/saucy/main/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/upubuntu-com/tor/ubuntu/dists/saucy/main/binary-i386/Packages 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/upubuntu-com/tor64/ubuntu/dists/saucy/main/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/upubuntu-com/tor64/ubuntu/dists/saucy/main/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
O que isso significa? Eu aprecio toda e qualquer ajuda! :)
Eu rodei o Ubuntu 13.10, eu o instalei recentemente e estou muito feliz com isso.
que é porque a fonte 64 não está atualizada, e não está pronta para get, codimension também, para cdrom, apenas desmarque cdrom na fonte de software, e lá você pode desmarcar as outras fontes até que esteja pronto para o arquivo.