I need to file for my advance parole as i want to leave US for travel shortly. I have yet to file for my adjustment of status, i.e. form I-485 etc etc.
Can anyone tell me if it is advisable to apply advance parole before or along with I-485? Or should I apply I-131 after I file my adjustment of status forms.

I don't think you can apply for AP before filing I-485. But you can file them concurrently.

But do u think I can expediate my Advance parole by applying it concurrently with I-485 in Dallas office? Usually APs are filed in Local INS officesas far I know.