grub screw

I have this very old front door which has dropped down and does not seal properly. I can see the bushes are perished so bought some new ones. Now how do I remove the door ? I can see the grub? pin and have tried knocking on it but its not moving. Anyone have any ideas ? Thanks in advance

Hi, I'm thinking I need to change the cartridge in the bathroom mixer tap. It's very stiff and only runs hot water. I've located the grub screw (I think) but can't make out what sort of key it needs. It appears to be circular as a opposed to e.g. hexagonal. I've tried a couple of allen keys...