1st, 2nd, 10th, and 13th are my favorites.
The 1st amendment is very important indeed. freedom of speech is vital to our form of government.
The 2nd amendment is necessary to maintain our right to self defense and to protect against governmental tyranny.
The 10th amendment is necessary to limit the scope of power of the federal government. Unfortunately the 10th has been rendered meaningless by the SCOTUS.
The 13th amendment ended slavery which contradicted the Declaration of Independence of July 4, 1776 In which was written the following words.
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.