Exclamation [Q] Lags after upgrade.

Hii Devs
I got an Alcatel OT X'POP running jb 4.1.1 with dual sim.
Recently I made an upgrade using ONE TOUCH UPGRADE S. Everything went fine until I discovered that my android got some randoms lags now and then. They are just random. some happens while chatting, exploring, others while playing etc..
So I'm trying to look for a Backup stock rom to flash.
Will that fix my lags ?
If so, where to find ? Because I don't have any, and I've been searching for like 2 days. Found one, "http://forum.xda-developers.com/showthread.php?t=2284347&page=28 " but it said to have a blacklight problem. If they aren't any, is there a fix for that blacklight?
Hope I get an answer soon, because its really annoying especially i went through all possible tweaks and in vain.
Thanks in advance.