compiz problem

[DIONISIS_POLITIS]

after the boot and the graphical screen, it flickres like to alternate the windows managers (compiz and the other). that happened after i replaced in mateconfig -editor the original window manager with compiz, because compiz didn't work at all (in Mint 9 worked with some minor problems, in MInt 13 doesn't work at all). it looks like the two managers struggle, neither prevails. and the system has become unusable. how can i fix it? (I booted in recovery mode to purge compiz, but i could not).
Thanks in advance.