On domestic flights that I have been (in India) there is no seat assignment on the ticket/e-ticket you purchase. It is at the check-in counter that you can ask for a window seat or a non-window seat and that's about it. I have never ever got the front seats and it seems pretty random what seat you will get.
I do understand that the front seats are the more expensive ones i.e. the first row as you have more leg-room than otherwise.
Can somebody share what happens when you are booking international tickets, does it have seat assignments on the tickets themselves or that is left to the discretion of the check-in personnel.