Learn English – the difference between “in” and “within”

Select means to carefully choose; it also means to use a mouse or keystrokes to mark something on a computer screen.

In both the cases, the number of things chosen or marked does not influence which verb is used.

Cooperating means working with someone in the sense of enabling: making them more able to do something (typically by providing information or resources they wouldn't otherwise have).

Collaborating means actually working alongside someone (from Latin laborare: to work) to achieve something.

The confusion comes from the overloaded meaning of "work with": In the "Work with me, people" sense, it means to go along with my idea - it's a passive condoning or suspension of disbelief rather than an active involvement. In the "I'm stuck, can you work with me on this problem?" sense it is a request for active commitment.

So in terms of helping achieve something, the ordering is something like collaboration, then cooperation, then passive indifference, then active obstruction.