The phrase "all right" means "not bad" or "pretty good". For example:

A: How was the conference?

B: It was all right. There were a few boring talks, but a couple of them were really good.

The meaning of "all right" can range from pretty bad to pretty good depending on the situation and how you pronounce it. If something is expected to be good, but you say that it's only "all right", then it might seem negative:

I saw that movie you recommended. I thought it was all right.

But if something is expected to be bad, saying that it's "all right" will seem positive:

A: How was your flight?

B: Actually, it was all right.