Hmm, but some games need data to run..

Added on March 27, 2012, 2:07 pmYes, Stock Rom has its own strength and weaknesses.
You should learn more about it before deciding which Custom Rom suits you.
Bear in mind, Custom Rom is not perfect too. In fact some are more buggy than stock Rom
wow.. already rooted..
this guide really simple.. thanks to the author
1. Download Odin and the correct CF-root zip file according to your firmware. To check, go to settings, about phone, scroll to the bottom. Look at baseband version, remember the last 3 letters, so let's say its XXKL1, then download the KL1 CF Root file.
2. Unzip the attached CF-Root-xxx-vX.X.zip
3. (USB) Disconnect your phone from your computer
4. Start ODIN
5. Click the PDA button, and select CF-Root-xxx-vX.X.tar
6. Put your phone in download mode (To enter download mode, power off the phone, then press the volume down+home+power button at the same time. Once you see the GT-I9100, let go of all 3 buttons. The phone will display "warning" and some text. Press volume up button to continue. Your phone should show an android icon and "downloading" text. This means you are in download mode now.)
7. (USB) Connect the phone to your computer
8. Make sure repartition is NOT checked
9. Click the START button
10. Wait for the phone to reboot
11. Done (if it took you more than 30 seconds, you need practise!)
Download Odin and your CFroot file here :
http://forum.xda-developers.com/showthread.php?t=1103399