You are in a restaurant with some friends. One of your friends receives a call and speaks to the person for ten minutes while sitting at the table.

Sei in un ristorante con degli amici. Un tuo amico riceve una telefonata al cellulare, e parla per dieci minuti mentre è seduto a tavola.

As long as the conversation is not intimate or crude, then it is fine, especially if the friend is talking to her mom or dad.

i think they are rude and need to go outside and finish the call.

I would ask my friend to leave

I would find it rude.

I would wish he would move and maybe pay attention to his conversation or start a new one.

It would depend on the formality of the dinner. In an informal setting I would not care. In a more formal setting, I would be angered.

kick them under the table

That seems pretty rude. I have a hard time imagining any of my friends doing that unless there were some kind of emergency.

Con un dito gli indico il mio orologio come per dirgli di sbrigarsi!

continuo a parlare con gli altri.

faccio finta di parlare pure io al cellulare e a fine serata dico: che bella chiaccherata!

gli chiedo cosa c'e' che non va

Lo lascio fare, d' altronde siamo amici. Mi sento autorizzato a fare lo stesso

lo lascio tranquillo avrà i suoi motivi