PokerTracker

Is there a way I can move all my hand Histories into PokerTracker4 from DriveHud2?

According to a post on their forums, if the site you play on provides hand history files, then you can import DriveHUD's ProcessedData folder into PokerTracker 4. The location of that folder can be found in DriveHUD's site settings. If the site you play on does not provide hand history files and the hands were captured by DH, you will need to manually export the HH files from DH and then import them into PokerTracker 4.