"As opposed to the other 3 parties who are all for unlimited third world immigration?"
Pretty much wrong on all three really. Though I wouldn't want to vouch 100% for the Lib Dems, but the Conservatives don't advocate this, and Labour are in power now and we don't have unlimited third world immigration, so they can't be.
"One cannot even criticize Muslims or homosexual behavior in the UK without facing prison."
You want to cite the law that you're referring to? Or give an example of someone who is in prison for this?