Create View - If ticked ON, selected Assembly View with defined settings will be created.
Create Detail View - If ticked ON, Detail View in the project will be created - not Assembly View. The View will be cropped to the size of assembly, but other model elements will be visible, as this is not a view of the assembly. See Create/Update Detail Views for more information.
View Number - In Smart Assemblies it's not possible to have the same Type of Views, like Front, Top, etc. with the same View Templates. If you try to do that, you get this message:
But if you set different View Number values for those views, then it will be OK:
View - Type of View that you want to create: Front, Top, Left etc., all default views available for Revit Assemblies, plus some flipped versions of vertical and horizontal sections, like Detail Section Left (B), Detail Section Back (A), and Plan Detail Up. Legend can be selected to tell the software that you want to have the selected Legend on the Sheet. See article on how to use Legends for more information.
Rotate - Select by how much the view should be rotated. 
View Type - Select view type or leave it as None, in that case default View Types will be applied, which in most cases is OK.
View name - Type in the name of the view.
View Template - Select View Template that should be used for the selected view to control visibility settings for that view.
Dimensioning Rule - Select dimensioning rules for each of the views. See more about dimensioning rules in related articles.
Tagging configs - create Tag configurations and pick one of them from the list to apply on selected view.
Read more about Tagging configuratoins.
Tag Elements - Tag all hosted elements if Tags of relevant category are loaded in the project.
GP is Visible - Select if Gravity point should be visible in view. It will only work if option to Insert Gravity Point is also selected in the Common Options tab. See more about Gravity Point in this article.
Update Views - If ticked ON, then Update Assemblies command will update this view after executing it.
Views are Visible - Position of section views, elevations by default are Hidden by the software. If it's checked, then they will be visible in selected view. NOTE: check also View Template if Sections, Detail Views are ON or OFF.
Insert Grids - if a grid line is crossing the assembly, 2D family of the grid line will be created in the selected assembly view. Read more about it in this article.