Complex sentence: He co-wrote "National Lampoon's Animal House", which Reitman produced, then co-wrote the Reitman-directed comedy "Meatballs"; he also appeared in the Reitman-directed films "Stripes", "Ghostbusters" and "Ghostbusters II".
Split into simpler sentences: He co-wrote "National Lampoon's Animal House", which Reitman produced, then co-wrote the Reitman-directed comedy "Meatballs". He also appeared in the Reitman-directed films "Stripes", "Ghostbusters" and "Ghostbusters II".