Default [Q] Actions GS701b

Hai there,
First of all i used this software called SRSRoot to root my chinese tablet. It said ROOTED.
But when i check it with root checker, the program returns not rooted.
Even when i try with adb shell su, the result is /system/bin/sh: /system/xbin/su: not executable: magic 7F45

EDIT: I tried with root uninstaller pro, but it don't works.

My second question is how to pull my touch screen drivers from the stock rom, because i want to install custom rom, but as i see, people are having hard time with the touch screen.

Sorry for my bad english.
Thanks in advance!