Hello again pete,
Real estate taxes are sometimes referred to as property taxes. I think maybe what you are thinking of is personal property taxes, and those of course are different than real estate taxes. But yes, on the line where TaxAct ask for real estate taxes (property taxes), that is where you enter the taxes you pay on your mobile home.
Further in the questionnaire they should also ask if you paid personal property taxes or other taxes. Personal property taxes would be taxes you were assessed on a car you own or a boat and trailer. Not all counties impose such a tax, so depending on where you live, you may or may not have personal property tax expenses.
As far as the interest paid on your home, it's not going to hurt you to enter that amount. TaxAct will ask you for any expenses you had at all pertaining to things like medical expenses, real estate taxes, personal property taxes, mortgage interest, charitable contributions and things of that nature. Once you answer the entire questionnaire on expenses, it will automatically calculate if you are better off to use the standard deduction or to itemize, and you should get a message saying something like --"Turbo Tax has determined that you will be better off to use the standard deduction". And then you need to confirm that you are in agreement with doing that.
Some people still itemize even though they end up with a lower amount than the standard deduction allows, and the reason for that is that depending on what state you live in, you come out better to itemize on your state taxes. But if you live in MT, this would not be a factor in your state. So if your standard deduction comes out to be the highest, that is what you will want to use.
Hope this helps.