Jesus said "be good, decent people", so what did Mohammed say that was better than that?
Why do muslims like Mohammed better than Jesus?
As for the final prophet, Mormons say Joseph Smith was a prophet, born 1200 years after Mohammed, so who shall we listen to, Jesus, Mohammed or Smith?
In response to your first question:
The Prophet Mohammed, peace be upon him, and Jesus, peace be upon him as well, both came with the same message. They both preached being good and decent people and most importantly being good people by fulfilling their obligations to Allah.
In response to your second question:
Muslims love all the Prophets, we are not supposed to put any Prophet down to raise another up. However, Allah in his infinite wisdom has selected and preferred some Prophets over others so that they have a higher status and better position. This article expands on the topic if you're interested:
https://islamqa.info/en/answers/7459/are-the-prophets-equal
In response to your third question:
To clarify: Muslims listen to both the Prophets Muhammad and Jesus, peace be upon them. However we do not follow the bible in it's current state as it has been altered and thus does not accurately represent Jesus' original message.
To answer the question: You decide who you listen to based on who is telling the truth, and you determine this based on the signs and proofs they have come with.
The bible states that the criterion to tell if a Prophet is truthful is to see if what he says has come to pass. Here is a list of Islamic signs of the end times, many of which have come to pass:
https://islamqa.info/en/answers/78329/the-lesser-and-greater-signs-of-the-day-of-resurrection