OP I would email the HR, Finance and IT director, or even the CEO, and copy your former line manager in.
Tell them that they have 7 days to arrange for a courier to pick up the equipment from your home at a date and time convenient to you and that after that you will disposed of it.
If you were made redundant and treated poorly you owe them nothing and I would not even bother to travel to drop this in the office.
if you had no response after 7 days, there are computer recycling charities that will take on equipment like this, wipe all the data and refurbish the machines if needed to then distribute them to kids/parents who can't afford to buy new equipment.
I did something similar with an organisation I had just left. They failed to collect the equipment, although they said they would, and then suggested I should drop it off. Since it was a PC and a laptop and I had no car there was no way I could bring that to them myself and I also did not believe it was my responsibility as I was a home worker and they had had the equipment originally delivered to me.
I told them I would not drop anything and that they had a week to collect the stuff at a time convenient for me of it would be disposed of, and that worked...