Well when i originally rooted, I did so without flashing a custom rom or anything. All I did was odin the root and let it do its work. I just want to have my phone rooted and still running the stock rom. The update i just did added the brightness control in the notification bar. This was an AT&T minor update. Once the update finished, i used a root checker and it said that my device was no longer rooted. Will I be able to flash the root and only the root? I just want to make sure before follow through with the process.
When you root via the process outlined in this thread, what you are doing is flashing a stock ROM with root injected into it already. So it's just like an OTA but comes pre-rooted for you. So this process is really more than just rooting your current ROM but is instead blowing it away with another ROM. It will still be a stock ROM but will likely be an older version forcing you to perform a factory reset.
Go into your Settings -> About and take a screenshot of all of the different version information and post it here (if it shows it, be sure to remove your ph# and IMEI for privacy reasons). Once I see that, then I can tell you more what to do. It's very important to post the version information of your current ROM. If it shows "I747UCALG1" then that link I have ~2 posts back should do it for you. If it's something else, then that link might not do it for you.