If your Android tablet is stuck on startup or boot screen, then bypass it using the following of the three methods. ( http://mytabletguru.com/techniques-to-tackle-android-tablet-from-boot-stuck/)
1) Press the volume up or volume down or home button when the tablet start, this is hit and trial method and might not work with all the tablets.
2) Hard reset : Hard reset the tablet by pressing the button combinations and this methods varies from tab to tab. See the following link to know more about the hard reset.
3) Flashing or Android installation: This method also varies from tablet to tablet. The tab shown in the video is flashed using LiveSuite software. To find out which flashing method works on your tablet see here