Hi..

I will buy the phantom 2 vision, should i upgrade it with the latest firmwire on everything before i fly it for the first
time?

Upgrade everything TX and Phantom, charge all batteries and do all calibrations before attempting any takeoff.  Read the manual and understand the takeoff pre flight.

My take is that it will work fine out of the box.  Read the manual and have a test flight - make sure it works - then update.  And I don't mean a huge flight, just a few laps of a field keeping full visual on it all the time.  I'm not saying you will, but people update right out of the box and then they are on here asking for help and for all they know the unit was faulty.

Then i will update everything before first flight and do all calibration

I've only had 1 crash and that was totally my fault.  I got to close to the 76' by 36' movie screen and the screen blocked some reception to the sats and the Phantom switched to ATTI mode without me realizing it.  The wind blew me under  the screen and put me into a tree in about 3 to 4 seconds.  I have it all on film.  A good learning experience.

My advice is to just read to manual, do the pre-flight checks and carry out the calibrations, wait for the Gps connections and then take off in a clear area away from buildings overhead wires etc. prop guards would be a good addition.  I haven't used updates since I got mine 7 months ago.