If there are no funds in the PTA and soon there will be no officers, then I think either way is fine. Both will have the same result.
At some point next year, the PTA will contact you looking for the dues dollars. Then you'd likely tell them that the PTA is no more (no $$, no members, no officers).
We have just switched our parent group to a PTO. Our money has been transferred, and we now advertise everything as PTO. We have not however taken the required vote to officially disband the old PTA organization. Our current officers are both PTA and PTO officers until July 1st, when the bylaws of both organizations state that the terms end. We just held elections, and yours truly will be president of the PTO next year. We had some hostility from the PTA camp during the transition, and I would like to take the final vote to close down the organization while it still has officers and membership. I don't really think we will have any trouble if we let it lie dormant, but just to be on the safe side, I'd like to officially disband. The current president is resistant to taking the vote for reasons he won't say.
Do you think I should push for the disbanding, or just let the PTA lie dormant?