No, there is a part where you bounce like Tigger but nothing major at all..and yes your seven month old niece can ride on someones lap..My Maggie was that age her first trip and I held her on my lap on almost every ride except for the ones with warnings and she was fine..
I hate spinning rides too, but love this one. I took my one month old on it last year and this year I took him on it when he was 11 months old. You'll love it!