i'm always more than glad to help
Now, on the rooting issue, I strongly recommend unlocking your bootloader and flashing a pre-rooted kernel. Why, you ask? Well, you'll find out eventually
Custom kernels often pack a bunch of optimizations and the ability to overclock. I strongly recommend Rage kernel for stock ICS. Once you flash it, i'll take care of rooting your phone on first boot. If you're not able to unlock your bootloader/don't feel comfortable flashing kernels, rooting by exploits is your only choice.
By the way, I strongly suggest giving LegacyXperia CM10.1 a try. Its awesome
Thanks a lot Pixelado. I have unlocked bootloader and using mesa kernel 4.8. Would Rage 3.2 would be better than Mesa?
I'll try LegacyXperia CM10.1 .. appreciate the recommendation.