You do NOT need a video capture card - what you do need is a firewire card in your PC - which it may already have - if so all you need is a 4 pin to 6 pin firewire cable. If you do not have a firewire caard in your PC there is a good option here :-
http://www.cableuniverse.co.uk/catal...roducts_id=782
which is for a card and cable together.
You will also need video capture and editing software - if you have Windows XP you will also have Microsoft MovieMaker - a beginners package supplied free but quite able to capture and edit digital video. Also if you buy the card above it says it comes free with Ulead VideoStudio which will also capture and edit video - or you can get a free trial of VideoStudio here :-
http://www.ulead.co.uk/vs/trial.htm
Do NOT be tempted to transfer your video to your PC via USB - you will be very disappointed.