Should it be "where" or "when"?

1. I have reached the point where I must make a decision.
2. I have reached the point when I must make a decision.

I'd definitely use "where"(and not "when") in that sentence.

By the way, you can often find the answer to such a question in the dictionary. For example:
where

This message has been edited. Last edited by: *Amy*,

This is very interesting, guys.

On a technical level, I agree with Amy that it should be a point where ..., but I just know that lots of English speakers will say a point when ...

The reason I think they opt for when is that they're thinking not of a place, but rather a time. We have the phrase a point in time, so that's why they're comfortable with using when instead of where.

For that reason, I think both are probably acceptable, at least at a conversational level.