LMFAO so you're saying you completely missed the topic at the very top of this section titled "MTA:mA v4.0" ?
If you'd read it, you would have seen this:
Running a server on the same machine you're playing on is a silly idea anyway, do you not have another computer you can do it on? And I doubt there will ever be a change to the current way minimizing is handled (completely disabled) unless the team can program in some way of making the game still run even when it is minimized.
How is it not realistic? I can lean out of the window and drive at the same time (though I wouldn't recommend it), so why can't a computer game character?
A lot of that is also dependant on processor power and memory availability. If you have a 1.5ghz processor and 256mb of RAM, don't even THINK of putting anything to max, even if you have something like a Radeon X1900 512mb.