James Marsters, a.k.a. Spike from “Buffy the Vampire Slayer,’’ still turns heads. The actor-musician, whose resume also includes “Hawaii Five-0,’’ “Smallville,’’ and “Caprica,’’ had fans captivated during his intimate concert at Super Megafest, a comic convention at the Best Western Royal Plaza in Marlborough over the weekend. Other VIPs at the fan event included Corbin Bernsen, Chewbacca Peter Mayhew, and Burt Reynolds. While there, Reynolds hung with some other guests, including former Catwoman Lee Meriwether and Dina Meyer from “Saw,’’ “Beverly Hills, 90210,’’ and “Starship Troopers.’’