Would attempting Russian impress my crush's mom?

There is a boy I have a crush on, whose house I'm going to be visiting soon for the first time. I know he speaks Russian fluently, and that he was born in Ukraine, but I don't know how much English his mom speaks. I am debating having a little bit of Russian handy (Hello, Thank you, etc) for impressions sake, but I'm not sure if it'd be appropriate, much less if I'd even speak it correctly, although I know a few things that a friend had taught me before. Should I have my list handy, or stick to English until I'm more familiar?