My mom submitted the I-130 form dec 2007. It got approved and is now sent to the NVC for visa processing. NVC is now asking for a $230 visa processing fee. My question is should I pay the $230 or can I just file I-485 as well as I-485 supplement A and submit it to USCIS?

You must pay $230 or your case would be automatically cancelled after 6 months from the date in the letter.