Which is better: to obey one's mother and buy the dining table, or not to buy it because it goes against the Sunnah, keeping in mind that it can be bought and used on the wedding day and then disposed of afterward?

We believe that obeying the mother in purchasing a dining table is more appropriate, because eating on it is not forbidden; at most, it would be disliked to the degree of karahah tanzeeh (disliked in a way that is not sinful but better to avoid). Obedience to parents takes precedence over avoiding something disliked (makrooh). Some scholars have explicitly stated the permissibility of eating on a table without any dislike.