Not many people use Jack The Grabber anymore. The two most popular ways of recording are...
Direct File Recording via a mount on the Dbox to a shared folder on the PC. You don't need server software running on the PC, and the files can be played back directly on the Dbox through Movie Player.
The other option is using Dbox WinServer. which can record to seperate video/auido streams, MPEG or TS files.
A forum search for "recording" should get you all the info you need.
There are other options, but those are the easiest and most popular, and Direct File is particularly good, but some XP users seem to have trouble with shared folders and opt for WinServer instead.