Yes, it comes with all cartridges but they aren't filled all the way with ink. Therefore, you will need to replace cartridges fairly quickly after purchasing depending on your printing activity.
Yes - it comes with a Cyan, Blue, Yellow, Black, and Larger Black one also. They are sealed up, easy to install (one of the easiest installs for ink that I can remember).
Some reviews say you need a usb connection in order to scan, is this true? will or will it not wirelessly send the doc to your computer? Normally, they do but i can't find where it says in the specs.
If you have a wireless connection you do not need a USB connection. However, it is nice to have it in case the wireless connection fails, but it is not required.
you can scan over wifi without any problems. I do it all the time. Make sure you use epsons scanning software. Handles scanning very nicely. Try not to use the microsoft scan features from the print screen.