What's the best pasta, and cooking approach, for making pasta salad?
I mostly use spirelli in pasta salads, but other thicker pasta works as well. I just cook them in a good amount of water (with salt/oil), nothing fancy really. But don't cook them too long or they will be too soft and not tasty.

I don't know about the packages in your country, but here, the time is always too short (you hardly can call it al dente), so if you cook it the time written plus one additional minute, you have the perfect time for pasta salad pasta :)

But it is of course a question of taste, so I would recommend to vary cooking times and see what you like best.