I think we're missing a bit of information from you.....
Are you asking if O2 or Sky do line installs (or enable old inactive BT lines) or are you asking if you can have phone line rental from companies other than BT without having to start the ball rolling by having a BT contract?
I assume you're about to move house (otherwise you'd already have a phone line, being an existing O2 Broadband customer).
Sky will arrange for a new phone line at the same time as setting you up with a Sky broadband account.
AFAIK this would be a Sky line, with calls & line rental charged by Sky, but would still use BE cables to get to your house (no other way I'm afraid - for close to 99% of the country it's either BT lines, with or without BT as your supplier, or cable TV).
O2 are planning on providing line installs (again; this would still be BT lines installed by BT engineers, but you'd pay the installation fee and line rental to O2)....but not yet

.
Ade
ADSL2+ with BE
DL Sync around 4.8Mbps
UL Sync 1088kbps
DG834GT with DGTeam firmware
Edited by adebov (Mon 14-Jun-10 18:10:23)