Q. Should one wear a Shabbat or any jacket for lighting the Chanuka menorah or at least put on a hat?
A. .Rivavos Efraim (O.H. 125: 7) quotes different sources for wearing special clothing for Chanuka.
Chesed Leavrohom (Vayigash) mentions that the choshen, the first of the special clothing of the Cohen Gadol, has the first letters (roshei tevos) of Ner Shel Chanuka. Since one who dresses properly for this mitzva, merits new and better clothing.
Nitei Gavriel (Avelus 1: 123: 3) maintains that an ovel should not change to special clothing for lighting the menora, even if he usually does so.
Kovetz Beis Aharon Veyisroel (y. 16; p. 116) quotes from Likutei Mahariach that the tradition of many Tzadikim was to wear Begodim Chashuvim for lighting the menorah. Tel Talpios (p. 46) mentions that the Rosh Yeshiva would wear a Shabbos hat.
Many Poskim maintain that for tne mitzva of birchas hamazon one should wear a jacket and a hat (Mishne Berura 183: 11), Ohr Letzion (2: !3: 3, et. al.).
Horav Shlomo Miller's Shlit'a opinion is that one should wear bigdei kavod when complying with a mitzva.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit'a