Ignore the xenaphobics.... okay, your wife to be will be entitles to NHS services as your spouse. She will not be entitled to unemployment benefits, social security or any other forms of government funds. She will, once she becomes your wife entitled to apply for a national insurance number, subject to having a genuine offer of work. She will pay PAYE & NIC but will still not be allowed to access any government funds. You will be responsible for her and her upkeep. Once you are married, you can begin the process of applying for an 'indefinate leave of stay' visa. Best place to be interviewed is one of the offices outside of London (Croyden). After three years of marriage, successfully passing the 'British Citizen' tests and 'English Language' exams she can apply for British Citizenship... which is also dependent upon time spent in this country and suitability... i.e. no criminal record etc.
Only after she gets British Citizenship is she entitles to recourse to government funds... i.e. Dole etc and after she has sufficient NIC contibutions.
How do I know? Well I used to work in the old Soviet Union...I married a Ukrainian and she is now a British Citizen... took a long time... but finally she was successful.... and don't be put off by those against foreigners... My wife has worked her socks off... built up a business here, employs people in the UK, pays PAYE, Employers NIC, V.A.T. etc and has not been entitled to anything except NHS services... which she doesn't use very often. If you need any further help... e-mail me and give me your e-mail address and I will try to answer any questions you may have.