Chinese tablet does not boot
If it is stuck in bootloop, I suspect corruption in /system. You should either reinstall the stock ROM or install a custom one. The first thing you will need is a custom recovery. According to this post by flowish at XDA-Developers, you can do this by follwing these steps:


  
  Download the recovery (recommended latest build) 
  extract and put to your /sdcard 
  open terminal applications (like better terminal
  emulator) ,or you can use from adb shell and type :

$ su
# cd /mnt/sdcard
# sh install-recovery.sh
# sh reboot-recovery.sh

  


Here is the button configuration of the recovery:


  Power button : Select
  
  Volume (+) : Up
  
  Volume (-) : Down


After doing that, install a new ROM from the recovery. Here is a custom ROM (from a post by nizar07 at androidtablets.net) that you can install from recovery.