Advice for Phone/Headset/Skype Setup

I'm looking for advice on what hardware &/or software I should get to allow me to have a wireless headset to use with my home computer and two landlines + skype (maybe).

What I have:
- WinXP computer
- Two landlines (Verizon) - one has DSL on it and used only for occasional outgoing. The other is a general use household phone.
- Skype - not used very much now, but I'd use it more if easier.
- USB to Bluetooth adapter (I haven't used it, but I have it)

Currently:
- the two landlines come to a two-line machine with a cordless handset. That machine is in the process of dying so I'd like to update while replacing.
- I use the speakerphone capability of that a lot while on endless hold to tech support, but (understandably) that irritates my wife when I actually talk.

What I'd like:
- Wireless headset so that I can be on endless hold quietly and have hands free while taking notes etc.
- Ability to switch between the two lines for incoming and outgoing calls
- Ability to use the headset with Skype (and ideally an opensource VOIP)

Advice Sought:
- Is it possible to put together a system that does everything I want smoothly? I don't care as much about the cost as about functionality. If so, what components would you recommend.
- If not, can I achieve it by sacrificing Skype? Again, what components?

If this is not the right place to ask I apologize - and would appreciate suggestions of where I should ask.

My thanks for any advice you can provide.

Jim Mitchell