Answer in Details
Chanting "Ram Naam" with sincerity and devotion is considered pleasing to Lord Shiva because he values pure devotion above all else. In fact, Lord Shiva teaches that taking the name of God with love and faith leads to liberation (moksha) and divine grace, regardless of the name—be it "Shiva," "Rama," or "Krishna."
So, if you chant "Ram Naam" with a pure heart, Lord Shiva will certainly be pleased.