Well
If you haven't been scared off the ESB poster at the top is a Style B 1980 studio poster (as best I can tell), measure the dimensions to make sure but they should be 27" x 41". That being the case it is worth around £100 give or take.
The other poster could be 'genuine' can't tell as clearly with the photos but the RoTJ might be a style B 1983 US 1 sheet, should be 27" x 40" to be sure, if so it is maybe worthy £80ish
The ESB in the middle could be a gone with the wind style advance Us 1 sheet, again 27" x 40" will tell you, if so then that is the most valuable £250+
The SW on the left could be a style B Us 1 sheet, again it will be 27" x 41" form 1977 not sure on the price there could be £125 and upwards, would need to research a bit more, but also this is a really, really well copied poster, bootlegs from 1977 are quite common for this one.
As for the rest not my thing. But if you have been put off but the banter you probably won't read this anyway.