Hi .... welcome to the Forum
Firstly, it does sound like the working clearance has been reduced over time (usually pressure of a foot resting on the clutch pedal) which has destroyed the release bearing and this is why it is screaming/rattling.
The clunking could also be the flywheel on its way out but you won't know until you get in there.
Rule of thumb is as everything sounds like it's worn/damaged, it is advisable to replace it all while you're in there as it is a false economy not to.
Let us know how you get on with it
Cheers Trevor