Which Speedlite for my Canon 600d I am new to Photography

Question

Which Speedlite for my Canon 600d
I am new to Photography
I am choosing between
a) Bower SDF680C Digital Flash for Canon SLR Cameras, Guide Number 139
http://www.adorama.com/BOWSFD680C.html
or
b) Bower SFD926C Dedicated Digital Flash for Canon SLR Cameras, Guide Number 125
http://www.adorama.com/BOWSFD926C.html
I want a Wireless Speedlite,
btw how does these Speedlites do the Wireless Connection with the 600d if they can ?
Does both use Slave Function, does both have Wireless Channel Selection.
Does My camera the 600d have Wireless Channel Selection by Radio Signal I know my camera has Slave Function Pls Help pls

Answer 1

1) My Canon 600d has a Slave Function and it does Not have any Radio signal or Infrared Wireless Connection between an External Speedlite ?
Correct, though I'm not sure it's called a slave function?  The 600D can use it's flash to trigger speedlights that are off camera, and set in slave mode.  But it has no Radio or IR signal.
The IR is something that is on speedlights.  As mentioned above, it's really just red light.  But it's used for focus, not for triggering flashes.
2) is the E-TTL just like the Operating system or Firmware of the 600D Flash System ?
TTL is an automated flash function, and it will be a function on a speedlight, not a camera (though you're cameras flash does have eTTL).  It lets the flash/camera decide how much flash power it needs.  In a nutshell, it fires a flash before opening the shutter so it can measure how much light it needs, then fires a second time with the shutter open to expose the scene.  It all happens very fast, you can barely see it.
Flashes will either come in manual only, or offer TTL in addition to manual.  Manual is just that, you choose the power level, and it fires during your shot.
eTTL is Canon's version of TTL.
3) Does the 600d have a Wireless E-TTL or something like that ?
As mentioned above, the 600D can use its on-camera flash to trigger other flashes, and yes, it can do it in eTTL. 
The down side to this is that the flashes have to be in the line of sight of the camera's flash (more or less).  [And it uses up your camera battery for the flash]  When you want to place flashes in modifiers or behind people, or screens or in a completely different room, it doesn't work so well.  So people use Radio Frequency transmitters to trigger the flashes.  It used to be an expensive thing to have, but now it can be done quite cheap, and quite reliable.
So the Only option I have for my 600d wireless connection to a Flash is
a) Slave Function.
b) I buy a Wireless Transmitter and receiver
 Pretty much.  You could also get a long cord to get it off camera, but it's really not a great option.