Izz, I run xp pro and a sony digital DCR-PC110E.
My cable is a 6-4 pin and use Movie Maker 2 to edit my movie. Have you used this? Re your question 4 pin out firewire card. If you look at click here search under 'firewire cable' they list a 4 pin so prosumably there must be a 4 pin firwire card. Don't know about the adaptor.
When I use Movie maker 2 i have full control of my video camera on screen. If you use this software I may be able to help, because I feel sure you must be able to use the cable you have.
Every little helps..Lap..