No worries
The rooms are great, nice to have your own ensuite/shower and more than enough room for everything you'll need. The rooms at durdham (the ones I've seen at least but can't imagine they vary much if at all) are hardly any different with just a shower door instead of curtain (which is better personally but really who cares
) and slightly more wardrobe space but apart from that not much between them to be honest. The kitchen at durdham is a fair bit bigger (2 ovens vs 1) and they have a nice lounge area joined to the kitchen so it is practically twice if not more bigger than the kitchens at UH which is nice but again doesn't matter too much in truth.
Naturally most of the 1st years live here in all sorts of halls, you'll meet people from your flat, from your course, societies, through mutual friends etc. and soon you get to easily know people in different halls. As for the social side, it truly is what you make of it. If you want to go out 4x a week or whatever you won't have trouble finding people to go out with. 95% of it is how you are as a person anyway, if you hide in your room all day then obviously not much is going to happen so I think this worry about this hall being unsocial, and that hall being social is not really relevant at all it's truly what you make of it, no matter who you live with or where. The same goes for meeting people in other halls, just depends on the type of person you are more than anything as to how many people you'll meet so can't say much about that but there is so many people I wouldn't worry whatever type of person you are
Yep there's also a great mix of people, I think 3 girls and 3 boys is the standard for flats in durdham and UH as far as I know, apart from gender specific ones which I'm not really sure about.
As for the UH ensuites being boring/excluded/whatever is pretty redundant too. What I noticed is the flats in the ensuites seemed to have mix together during the beginning just naturally being next to each other and all and some have made great friends but various people know links and such to other flats and it's all fine and if you wanna have a go out or whatever there's always people about and such so really not much to worry about that either I say personally so if you really want to go for an ensuite but are scared about having a boring dead halls, just go for it, you'll be fine! I say the same is true for the durdham/dulldham stereotype, there's so many people in durdham who are just as normal and go out and whatever few times a week I think the stereotype is vastly over hyped and you'll probably realise that when you get there. Of course there are quiet people who stay in their rooms never come out, but you get that in every single halls, the truth is how your flatmates are is complete luck, but if you don't mix that well with them there are so many people around you'll get to know in freshers so there's not much to worry about it
Hope that's helped a bit any more questions feel free to ask