have you looked at the immigration website for the usa? they wil tell you what kind of visa you can get, or if your quals/experience will qualify you for it. you usually have to have a job offer to apply for a immigrant visa 9or have relatives over there)
see here
http://www.usembassy.org.uk/cons_new/visa/iv/i ndex.html
as you can see - it's hard!
What makes you think it will be a better life for you? even if you got a visa, your fiancee may not be able to come straight away