Hi, I think I somehow managed to brick my wife's S2.

It currently can only show Galaxy S2 starting logo with yellow triangle warning at the bottom, can not go further than that.
I can to make it go to downloading screen and put Jeboo kernel though Odin, but it still can't go further than the Galaxy  S2 logo screen with the triangle yellow warning sign.

As you may able to guess, I did root the phone, and it went well until I tried to do a factory reset inside the phone's setting menu, now I realized that probably wouldn't working as the phone been rooted and the stock Telecom Android 4.1.2 probably wiped out Jeboo kernel/ and the Jebo kernel need be loading before the stock Android? Not sure exactly why, but somehow the end result is trying to reset the phone inside the stock Android destroy the whole loading chain after root I guess.

The question is, what is the easiest way to make the phone come back to a usable state, preferably to the Telecom stock 4.1.2 as this is not my own phone and I want it maintenance free.

I did managed to make a couple of  backups to external SD card inside CWM I believe(text menu after Volume up + Home + Power), and it would be ideal if I can recover the from those backups. But obviously, I couldn't restore from that backup if it can not pass the start up screen. Could I do that though Odin?

No objection about install custom ROMs, but really, I just want root it, don't want change the stock ROM unless I have to, or it is much easier just install a custom ROM.

I only did root my Milestone phone once and it went well, but I am just following instructions and as it went well, I am pretty much a newbie to the who root/ROM thing as I am just following instructions step by step and didn't learned much.