Exclamation [Q] Stock Rom Restore in GT I9100 to deal with boot stuck screen

Hi Everyone,

First of all I would like to apologize, if I am repeating any question. I tried many threads but I couldn't understand completely. Hence I am afraid I need to ask individually. Hope thats fine with the community.

So, I own a Samsung Galaxy SII since last 27 months. I bought it with Orange on a contract in France and the company unlocked it many months ago since I do not live in France anymore. I have never flashed the phone with any other ROM, or provided root access or anything else. I have always used Kies to update the software. If I remember correctly the phone currently has Jelly Bean on it (4.1.2 I think). It doesn't have any external SD card, just the internal memory.

Due to some unknown reason, since yesterday the phone is not able to boot up. Its stuck at "Samsung GALAXY S II GT-I9100" screen. I tried to used Volume up+Home+Power keys to go into recovery mode which is not possible. I also tried to go in Download mode using Volume down+Home+Power keys which is possible. Then I tried to connect with Kies to connect it but after 15-20 mins Kies gives error in recognizing the device. When I open ODIN 1.85 (I guess that is the version which should work with my phone), it does shows "Added" status for the device.

Now after reading many posts I have realized that restoring to stock rom would resolve the issue, but it still dint for many. What is appropriate way to deal with this problem. I found some stock rom on the page of mobile network comparison webpage , but I am not sure if I should use it or not. Also I am afraid if I should check the region/model etc for this. I guess I should only install ROM which lies in France-Orange category.

I do not care about any data since I back up my phone from time to time. But I do not wish to play around with the phone much, unless required. However I would appreciate if there is any way to restore the contacts and message stuff.

Thank you very much for your help and support. I highly appreciate the effort.