Question [Q] About flashing from CWM

i want to know how to remove mods i have installed using CWM recovery. let's say for example i flashed a mod for transparent bar in my MMX canvas 2. now how do i get rid of it? how do i recognise the files installed after flashing? also help me in kernels. is it ok if i use a 4.2x kernel in my stock 4.1.1 jellybean rom? i look forward for a reply which explains me and clears my curiosity.

Thank you!