I tried to explain this but it got too complicated as I was typing so I deleted it :| I suggest you watch a bunch of YouTube videos to learn a bit more but here are some highlights to keep in mind.
-Timecode allows you to use your CDJs to manipulate Traktor on your laptop.
-Traktor Scratch Pro 2 is what you need to use timecode.
-Traktor Pro 2 is the software alone (I believe) which can be used with external MIDI controllers.
-If your mixer is not "Traktor Certified" then you will need an external, compatible sound card that will allow you to use this setup.
-The X1 is a Midi controller (no sound card) which allows you to control Traktor (or any other DJ software) on your laptop. The one reason why it may not be a one stop shop would be mainly due to the fact that it is for deck control without a jog wheel. so all you have is play cue loop etc. controls. No mixer control.
Feel free to ask any more questions after you do some research and I will try to help you out.