Sorry if this is a noob question. I just got Steam, and I need Half-Life to play NS. I already own the disk version of Half-Life, can I use that instead of buying the online version?

short answer:
sorta.


Long Answer?

there is an option in steam for 'activate a product on steam'.

Open up the My Games tab, it is on the bottom. Start that up, punch in your HL CD key(s) and then download the game with Steam. You do HAVE to download the game b/c NS will NOT run on a copy of HL that has not been patched all the way up (And the only way to do that is via Steam).

Assuming you own a legal copy of HL, and have not had your CD key banned before, then you are good to go. If you do have problems, then contact Steam support at Steampowered.com.


Enjoy

i believe you should be able to activate halflife through steam using your old cd key from the cd version.

i know its possible to use an old halflife cd with steam, i do it now. i dont remember exactly how i did it, but i think i just activated halflife with my cd key

Yes you can.

See: http://www.unknownworlds.com/forums/index....t=0&start=0