You may be relieved to hear that you don't need any BT software to get a PC on the Internet. If you run the CD you're after then it'll install loads of startup programs that you're unlikely to want or use.
If the PC in question is connected via an ethernet cable then simply plug it in and away you go. If it uses a wireless connection then you'll find the network name and associated password details on a sticker on the BT Homehub and/or the plastic "credit card" that came with the router.
Doesn't really answer your question but I hope it helps.