Check with an accountant. I'm not an accountant, so this is not tax advice. However, my non-professional comments are:
No, you can't write off the taxes. You don't own the house and you're not paying taxes on it. And you can't put the taxes in your name.
You should have renter's insurance. You can't get owner's insurance on a property you don't own.
What if you make your payments, but the seller doesn't pay the taxes or insurance? Your lawyer should have given you several options or suggestions on how to prevent that. (Oh, you didn't have a lawyer? Big mistake.) Still, you may be able to check with the county periodically (for instance, twice a year) to make sure that the taxes are paid. As far as insurance goes, ask the owner to provide you proof. Either that, or ask the owner to sign a document authorizing you to contact the insurance company and authorizing them to release the information to you.
What you should do right now is to take all the documentation to a good real estate attorney and get his advice on how to protect yourself. That would have been a lot more effective before you entered into the agreement. But there are still some things you can do.