Sanatana Dharma (SD) is a philosophy. As the name implies, it means "The eternal way of life". The way of life on a micro level is to adapt your environment. On a macro level, it is the development of a way of life that lasts mankind for eternity. That does not mean, zero population growth and agarian society. The other part is understanding creation, nature and enjoying nature as Rig Veda presents. Though there is a wonderment present as to who created the creation, the search continues because, Rig Veda did not spell out specific nature and property of the creator. As you know, the word "Worship" means the reverent love and allegiance accorded to a deity, idol, or sacred object. SD only allows the reverence to mother nature and the creation and wonders about the creator. God, deity, idol and sacred objects are manmade concepts and subject to change over time. I do not know anything about the "Arya Samaja". As the name implies, it is a group (Samaja) about the civilized (Arya) ones. Metaphorically, if they are civilized as opposed to barbaric or dravidians (south indians), they should not be worshipping idols like non-aryans. BTW, Buddha never acknowledged the existence of a specific God. In fact he went back to the roots of Rig Veda - atleast tried to, while his followers colorized the teachings. And majority of Indians do worship many forms of deities, idols etc - it is integrated into culture mor so than it is a religion. Five hundred years from now, we will be doing the same with Easter egg hunt and rabbits and Sanata Claus. I wonder if there will be a religion that will spring up around Santa!