Question / Help Streaming Gameplay And Facecam Of Someone Else!

[osinedges]

So I know how to set up the two videos add source ect. but what i need to know is what the best settings would be to have as little lagg as possible while streaming both? audio is priority. here is my system spec:
Operating System: Windows 7 Home Premium 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.130828-1532)
Language: English (Regional Setting: English)
System Manufacturer: ASUS
System Model: All Series
BIOS: BIOS Date: 09/12/13 10:12:15 Ver: 08.06
Processor: Intel(R) Core(TM) i5-4670K CPU @ 3.40GHz (4 CPUs), ~3.4GHz
Memory: 8192MB RAM
Available OS Memory: 8130MB RAM
Page File: 4238MB used, 12020MB available
And my graphics card is as follows:
Card name: NVIDIA GeForce GTX 760
Manufacturer: NVIDIA
Chip type: GeForce GTX 760
DAC type: Integrated RAMDAC
Display Memory: 4038 MB
Dedicated Memory: 1990 MB
Shared Memory: 2048 MB
Current Mode: 1920 x 1080 (32 bit) (60Hz)
Monitor Name: Generic PnP Monitor
Monitor Model: 2250W
Monitor Id: AOC2250
Native Mode: 1920 x 1080(p) (60.000Hz)
Output Type: DVI

MY internet speed is this:
http://www.speedtest.net/my-result/3218149230

ALSO!!
I will only be streaming minecraft as of yet so if any settings i could change on that that would help, please let me know!

ANY HELP IS GREATLY APPRECIATED!

Many thanks guys!

 

[dodgepong]

When you say "lag" are you talking about game FPS performance, game latency (high ping), or stream stuttering?

Have you looked at this site: http://obsproject.com/estimator