Thank you fdpower for the info, i had to mention UK as i had to give my last 10 years adress and work info and on top of that i need to take my old passports to interview as well, and also it said that lying in application is a federal crime, apart from living illegally i have no any other criminal records and i assume as i am applying for immigrant visa that should not hamper it but like you said apple/oranges gore haru ko k bhar, j huncha aba bichar garna parla.