High mileage CRV

[Germs]

I have a diesel CRV which is approaching 140k miles, to date it has been entirely trouble free other than the air con which has packed up twice - the last time permanently! As it is worth nothing to anyone but me I'm now doing my own servicing, just a couple of questions if I may:

has it a timing belt or chain which might need changing?
other than engine oil should I be changing any others - gearbox or diff?

As an aside I know it has a dual mass flywheel/clutch - does this mean if the clutch should need changing it is more complicatewd than just a new clutchplate?

is there anything else I should take note of?

Thanks in advance for any advice.