With you computer you can edit video, BUT to render the finial production may take overnight to finish. When I first started getting into video editing the pc I had at the time was the same as yours, a 5 min viedo could take 30~40 min. complete. Make sure that you get a DV camera that will pass analog-DV passthrough then you can use it convert your old tapes. You will need a firewire card.Also check out this link from user timwerx. John
http://www.timwerx.net/odds/pcfile.htm