Who is Obligated in Parashat Zachor?

There is a biblical commandment to remember what Amalek did to the Jewish people and this is fulfilled by reading Parashat Zachor. In fact, unlike the Torah readings of Shabbat, holidays, etc., which are rabbinically mandated, there is a Torah obligation to hear Parashat Zachor (and some say, Parashat Para as well). The Shulhan Aruch (Orah Haim 685:7) adds that if one does not live near a synagogue, one should make a special effort to listen to the Torah on Shabbat Zachor. Parashat Zachor is read on the Shabbat that precedes Purim since Haman was a descendant of Amalek.
Regarding a woman’s obligation to hear Parashat Zachor, Sefer HaHinuch explains that since women are not obligated to go out to war and would not be involved in wiping out Amalek, they are exempt from this Mitzvah. This is also the opinion of most rabbis and the custom in Morocco was that woman did not go to the synagogue to specifically hear Parashat Zachor. As well, since there is doubt as to a woman’s obligation, the Torah should not be taken out especially for a group of women. Nevertheless, the Kaf HaHaim (Orah Haim 685:30) says that although women are exempt, they may read Parshat Zachor for themselves from aHumash.
Ideally one should hear Parashat Zachor from someone who reads it in the pronunciation to which one is accustomed, such as Sephardic, Ashkenazic or Yemenite. Furthermore, Rabbi Ben Zion Abba Shaul (Or LeZion vol. 4) says that one should hear Parashat Zachor from a Torah that is written according to one’s tradition, since there are differences in script between the Torah scrolls of different communities. Nonetheless, if one hears this Torah portion from someone who reads it in a different tradition or from a different community’s Sefer Torah, one still fulfills one’s obligation.
Summary:   Listening to Parashat Zachor is a biblical commandment and one should listen to it in the style of one’s tradition. Women are exempt from listening to Parashat Zachor.