wretched auto-correct.... wellies!
It really sounds like you are struggling with the other mothers not being what you expected.
You don't 'need' to socialise with other mothers at the school - how about getting involved with cubs or some other activities for children in the area?
Also, you will need to give it time. When DD went to the school, friends who knew of it said 'ah, you are going to be THE middle-class mother, and with your accent...' which made me panic a bit. I didn't want to be perceived as snobby or anything, but given I'm a bit shy it was likely to happen, plus everyone else seemed to have lived in the area for 5 generations and all knew each other already. Most of them were in social housing and we were in a yuppy flat. I was sure they would all hate me - let alone would I like them!
Children don't have those kind of issues at this age, and DD was very gregarious and popular which really helped. Even though she's now at a different school, we still invite some of her old friends to birthday parties.
To bring my inner-snob out... yes, she developed a cockney accent, yes, she learnt to say toilet, and wanted her ears pierced. But, she was happy, having fun and learning.
When it came to primary applications I actually listed it above 2 Outstanding and much more MC schools.
There are also bound to be other parents more like you. DD's current school (that we were desperate to get a place at - and did via the waiting list) has over 70% FSM. But in her class are children whose parents are doctors, architects, sculptors, marketing directors for big companies - you just don't see them often at the school gate as kids are at after-school and breakfast clubs.
DD only gets one book a week - but is expected to read every night at home. They also only read 1:1 in class once a week which I was very 
about initially. It does seem to be very normal. However, 88% of the kids get L5 at KS2 (and nearly 80% are EAL) so they're obviously doing something right.
Not sure what's wrong with Gangnam style? If it gets them all dancing around and enthusiastic then great.
Reading your posts, it very much seems that you are mourning the life and friends you have left behind and that will make so many things look worse than they are. Little things (like Gangnam - that you probably wouldn't have batted an eyelid over at the old school are now assuming far greater proportions). Very normal way to feel, but you will need to make some compromises if you are going to have the house etc. Go and look at the other schools, go and look at the private school, but be sure that you are making choices with your head as well as your heart.
That said, it may well be the worst school in Britain and you should get the hell out asap!