There would never be a full moon.
It would fall to Earth's surface.
The boat would make no progress.
It won't; a moving object has the object to continue moving. If one day the Moon mysteriously and suddenly stopped moving around Earth, it would fall upon the Earth pretty soon (in a few days), due to Earth's gravity.
Since everyone and everything on Earth does so anyway, nothing.
it will go same speed forever without affecting mass and weight
Earth's Gravity would pull it straight down to earths surface.
Earth's Gravity would pull it straight down to the Earths Surface.
The gravitational pull of the sun would not be balanced by the outward force derived from the Earth's centripetal motion, and the earth would fall into the sun.
No shift under those conditions.
Stopped moving... With respect to what? Any movement must be specified with respect to something. Anyway, if Earth stopped moving around the Sun, the Sun's gravity would attract Earth towards the Sun - i.e., Earth would fall towards the Sun. The time it would take the Earth to actually reach the Sun can be calculated using Kepler's Third Law.
IF a wave moving at a constant speed were to have it's wavelength doubled (Wavelength x 2), then the frequency of the wave would be half of what it originally was (Frequency / 2).
It would keep moving at a constant speed in the same direction forever, or until it hits another object.