I am us citizen since 1991 and then my two boys are also us citizen, I applied US residency for my wife during 2002 and then I couldn't follow and then I received a letter noting my application has been cancelled, now I want to apply for her again, since I did not complete my forms and did not continue the procedure, Should I mention in my application about my last request or since it has been cancelled, no need to mention it.
Thank you

Make sure she is eligible for adjustment of status before filing again. If you post more details we can assist better. Or consult with an immigration attorney.

You must note it on the forms. The USCIS will know, and it does not prejudice your case. What will prejudice the case is you intentionally omitting the information.

File now, follow up and get it done.