Connecting Laptop to Mixer

Question

There seem to be several ways to connect my laptop (MacBook Pro) to my mixer (Yamaha MG166CXUSB) but I don't know which one would be best for just playing into my IEM's.
Using the Search function I've read several suggestions for connecting the two including Headphone to RCA and USB to USB.
I'm using a Roland TD-12 with electronic toms and kick pad to trigger sounds on my laptop (Superior Drummer 2.0 VST's) along with an acoustic snare and cymbals that are mic'ed and connected directly to the mixer.
Signal path,
1) Roland TD-12 pads/kick->MIDI to USB cable->Laptop->Mixer->IEM's.
and....
2) Mic'ed acoustic snare/cymbals->Mixer->IEM's
On the MBP, I have tried connecting the headphone jack or USB, both seem to work ok. The mixer can receive the signal from my laptop several ways that I know of, what I don't know is which way 'should' it should be connected. So far, all of these connections seem to work (ie I can hear the drums play in my IEM's)....
1) Headphone out (MBP) to Mixer '2TR In' (RCA Jacks), or
2) Headphone out to 'Line Input' (TRS Jacks), or
3) Headphone out to 'Insert' (TRS Jacks), or
4) Headphone out to 'Line Input' (RCA Jacks).
I can also use the USB 2.0(MBP) to USB 1.1 (Mixer). I think the USB port on the mixer is there more for connecting a computer for recording purposes rather than playing live, I could be wrong though. I know USB 1.1 is rather slow but how does it compare to using the RCA or TRS jacks in terms of speed?
I have a Firewire port on my laptop, should I be using that to connect to the mixer?
I don't have much experience with mixers and I really don't know from reading the manual what the connection should be. I can hear the drums in my IEM's using any of the above, but which connection 'should' I be using?
Here's a list of the connections on the mixer and the corresponding Page/# in the Yamaha Manual.
http://www2.yamaha.co.jp/manual/pdf/pa/english/mixers/mg206cusben_oma0.pdf
2TR In Pg21/#5
Line Input Pg16/#2
Insert Pg16/#5
Line Input Pg16/#4
Thanks
Mike
Message was edited by: Codeseven7

Answer 1

That's embarrassing.
it happens more often then you'd expect, don't worry about it.
Does it matter that I'm using the computer's line in rather than a USB/Firewire?
you could debate this for hours, really. a good quality firewire interface could, in theory, get you a better recording, but my stand is that your technique and skill as an engineer will affect the quality of your recordings far more.
in particular, if you're just starting out, you've got a lot to master (recording, mixing and perhaps mastering if you're willing to go that far). concentrate on that. if it sounds good to your ears, then you're fine.
look at it this way, apple has sold, what, over a billion songs via iTunes? most people are quite happy with those, and they are far from high quality. as long as your ears are satisfied, you're gold. if you're not, we can certainly offer suggestions for a FW or USB interface.
(the only other reason would be if you wanted to record more than two tracks at a time, for that you'd want a FW interface for sure)