Not sure if this still works ?? (i believe sky put some update to stop the software?) ... might work...Might not..
software needed
Copy+ & +Extracthttp://www.skycopyplus.co.uk/extract.phpremove
Hard drive from sky box & connect to PC (via usb cable or internal connect)
Start up +Extract and select your disk (should be shown with green tick)
Select the program's you want to extract (for this method only the FTA ones shown with green icons are worth extracting)
Select an extract location in the right hand pane
Click "Actions" on the +Extract menu and "Extract Selected Recordings"
After extract is complete in +Extract you can use "Tools",
"Convert STR to MPG"