Bro, you NEED to check out Virtual DJ!!!
http://www.virtualdj.com
It does all you ask and more. It's user interface kills Traktor and Serrato and PCDJ. It does alot more too ala samples, FX, etc. You can even control video with it and mix video like MP3s! Kick ass!
There are a few different options of licensure and hence different tiers of cost.
Honestly, you do not even need a MIDI controller to do a one night stand with this app. It is so damn easy and intuitive.
(1) Buy the basic package
(2) What type of soundcard are you using? If only a RealTek or onboard soundcard you cannot cue. 2 soundcards is the way to go.
If you have only one soundcard get an iGriffin <Google for it> as it is a very inexpensive but effective USB soundcard with 1/8" stereo in/out. This device will let you send your main outs to your friends home stereo system and allow ytou to CUE through the iGriffin.
NOTE: For the main outs you can also get a 1/8"->RCA pair crossover cable ($15 U.S.) and then connect that to the TAPE IN of any mixer, then send the sound to a PA system or Active Speakers.
Virtual Dj is the only software package that superimposes both sound waves of 2 tracks on top of each other, in different colors. The benefit of this is that you can "see" the big waves of each track and really fine tune a crossfade in a hurry if you have to.
I have a small DJ business here, and I use VDJ with a Maya 44 mkii soundcard (4in/4out, 1/4" TRS connectors/PCI card) so I can send one output to my headphones and the other I use a stereo splitter and go right out to my Carvin PM15A active speakers. The inputs of the Maya 44 can be used to receive timecode from your 1200s if you have the VDJ timecoded vinyls ($40 for 2). Or, you can buy a really nice PCDJ DAC3 MIDI controller (about $350) to control all of the functions of VDJ from an interface that is just like using 2 CD players.
Download the demo now and give it a whirl. You will shit your pants with glee because it is so fun, so easy, and so powerful a program.
Feel free to shout at me if you need any more info.
Regards,
-Alex