Wireless Connection

Hi
I have a PC with BT Basic Broadband package which is working fine.
I have purchased a new laptop with Windows Vista and Wi-Fi bulit in, and I have a wireless modem I have never used (still in the box) which i received from eircom, can i connect this modem to my old PC and use it as a wireless connection in my house for my laptop?

any help would be appreciated..

This depends on exactly what you have and then on compatibility with BT.

Do you have a wireless Router or a wireless Router/Modem?

If the former it connects to your BT modem and then you need to bridge the modem to the router.

If the latter it would replace your existing modem and would require compatibility with BT.