What can you tell me about custodial accounts and UTMA regulations?

I am a minor who is very interested in starting my own account, and opening my Roth IRA very early. My major questions deal with UTMA age requirements, if I am allowed to use a bank account that my guardian/custodian's name is not on, and whether the et is considered my own even if I am not of age (my mother is worried that it would be susceptible to marital et law in her separation, but I believe I own the rights, even if I don't control the account). Any information is helpful. Thank you