Yeah, if it is still stuck, flash the ROM back. (how?)
1. Install USB drivers.
2. Download ODIN.
3. Download this file and unzip it using WinRAR.
4. Load the files in ODIN (files have names, choose corresponding ones in ODIN)
5. Boot the phone in recovery - Shut down. Press volume down + home +...
What you need to do is-
1. Get the USB drivers for your tab.
2. Install ADB - look around on google, you'll get it.
3. Connect USB and change directory to ADB folder.
4. type "adb reboot recovery" in the command prompt.
5. Do a factory data reset - you can do that once recovery mode boots up by...