Truthfully, I'm not clear as to exactly what you're asking. For one thing, wine and the x-window graphics server are separate things. First you run an instance of X, then when you launch a gui program, it uses X to create the windows. So your total system burden is equal to one X session plus the programs you run.
As for wine, all it does here is take the graphics api calls of the windows program and translate them to equivalent X calls.
Now concerning running multiple instances of a windows program under wine (note, you don't "run wine" by itself; it's just the environment emulator), it depends on the program. If it's possible to run multiple copies of the program on windows, then you should be able to do pretty much the same thing under wine. If the program is such that it will only allow one instance to run at a time, then you'll have to set a different WINEPREFIX for each instance you want to run so that each process uses its own wineserver. See the man pages for wine and wineprefixcreate, and the rest of the
wine documentation, for more.