Why people look up to him:

Jackson was one of the first popular presidents, in the sense that he believed in expanding participation in the vote and politics and did a lot for expanding the idea of "Democracy" and mass participation in politics by all classes, among other things launching the first real massive presidential election campaign. He basically founded the Democrat Party(the jackass that is still their logo comes from an insult aimed at him that he appropriated). When he was president he also helped prevent a civil war during the nullification crisis. He also drastically expanded the power of the presidency by among other things using the veto against laws he didn't like rather than just against unconstitutional ones( most people these days would say that was a good idea). He was also a great general for the US, winning a heroic victory while massively outnumbered by the British at New Orleans and conquering Florida, won many duels, and is often considered a symbol of a "badass" which people tend to like. He also paid off the debt(the only time in US history) which some people think was a good thing.

BUT:

Jackson's Democratic expansion was very much White Men ONLY. Jackson held slaves and believed wholeheartedly in slavery. He hated the Native Americans and led the US on many phases of slaughter and land appropriation against Native American tribes (many of whom had treaties with the US), culminating in the Trail of Tears that forced the Cherokee off of their land and into Oklahoma. Some go so far as to call him 'genocidal' towards the Native Americans. As president and as a human being he was also incredibly abrasive and vengeful, for example, his paying off of the debt was part of a political campaign of his to destroy the US Federal Bank because he didn't believe in it philosophically and it was supported by his political rivals. This caused massive economic recession that defined his succesor Van Buren's term(it is actually beneficial for a state to have some debt). Once during a pistol duel he waited for his opponent to shoot first (against protocol) so that he could take his time aiming at the man's genitals, killing him with the shot.

People tend to only have one image of him in their head.