Shabbat Zachor is one of a handful of Shabbatot where the Torah is set up to reinforce the message of a holiday. This Shabbat is meant to remind us of why Haman is about to lose yet again, (though some think this might be his year ;-) ). In looking at the bad guys we remember, we can also learn moral lessons for ourselves, specifically regarding how we deal with enemies. We might even find that God forgives those who we might not.
Shabbat Shalom
Saul
Amalek
Agag
Purim