suggest an explanation for the ideal nature of helium compared to the other gases

Answer 1

2 electrons fit it that first shell. Helium has exactly 2, no extras and not short any. Therefore He does not want to combine with other atoms, including another He to form a chemical compound or molecule. Therefore called "noble".
Hydrogen for example has ONE electron in the shell that would hold 2 and is therefore likely to react with other atoms, even another H to form H2 but Helium gas is He NOT He2