There are different ways a DUI lawyer can get BAC evidence excluded, and I won't bore you with the details, but get one in your city. Avvo has a terrific "find a lawyer" tool to find a top-rated lawyer with a low fee. Good luck.
Absolutely. You never want to try to deal with the insurance company yourself or you will get a tiny nuisance settlement at best. Find a lawyer with a low contingency fee, less than 30%, so you are left with the lion's share of the settlement, not the lawyer.