Bird identification needed.

I'm wondering if someone can identify these birds. Firstly, there was a flock of gulls causing a commotion at the end of my street for no reason I was able to discern. Not sure what they are though. Perhaps mostly juvenile? But anyone know what breed?

Secondly, the two black birds on my fence were visitors to my garden (bullying the pigeon on the ground feeder). I'm almost certain they aren't jackdaws and wonder if they are ravens, as I suspect, or actually crows? Not sure.

Denise