How to send raw data, without USB protocols, handshakes... to USB port on Windows 7 using C or C++?
You don't. The closest you'll get is using libusb.
Most parts of the protocol are handled by the driver and the IC.
If you want to do raw USB, just bit-bang it on an AVR/Arduino or do it using an FPGA.
The shield does the same abstraction by adding a controller IIRC
Take a look at the V-USB library for AVR. It can also run on the Arduino.
You'll have add some components on the port (see pic), but it's not extremely hard.