MPEG is highly compressed and not made to be edited
Go to the section of my notes file concerning editing compressed files to read why
Either obtain an edit type file, or convert the MPEG to DV AVI type 2 with 48khz 16bit sound outside of Premiere
Realize you will take a quality hit in converting a compressed file to an edit file
Welcome to the forum.
I've got one question, regarding this statement,
But when the edited file is exported and viewd on TV screen, I notice flickering issues when we have fast movement camera or people.
How are you displaying the AV on the TV? Are you going to a DVD/BD, or is the TV hooked up to the computer?
There might be some Interlacing issues, and some improvement might be possible, but like John T. states, MPEG is not an ideal source to begin with, due to the heavy compression. If you then go to DVD, you are compressing yet again, and what you see is an artifact of the multiple compression used.
Good luck, and let us know more details about your display/delivery.