New to zucchini

I've planted zucchini before,  grow lots of leaves, and no fruit.
This year seems to be different,  one fruit is growing gang busters with others coming along nicely.
Only thing is , the fruit keeps getting bigger but its still mostly yellow.
Should I ahead and pick it?

yup. go by what size you’d like, not color. green zucchs usually don’t start yellow, so i’m not sure what the deal is there.

Cool, we pulled it.
I think I bought this plant, the only squash seeds I've tried to start come from winter types.
Half yellow fruits don't seem like a trait to breed for, but if we get lots of them,  I will certianly let one grow out for the seed,assuming they taste ok.

I've had zucchini that looked similar to that before. It happened because I planted them too close to yellow squash and it cross pollinated. I didn't like the taste or texture of those so I'm careful to plant all squashes far apart. How did yours taste? If you created something good, save the seeds and get even more creative.