The Best Episodes Directed by Peter Chakos
#1 - The Lunar Excitation
The Big Bang Theory Season 3 - Episode 23
While Penny worries that dating Leonard has ruined her for normal guys, Wolowitz and Koothrappali search for Sheldon's perfect match online.
8.22 
#2 - The Parking Spot Escalation
The Big Bang Theory Season 6 - Episode 9
Sheldon and Wolowitz's fight over a parking spot at the university impacts the whole gang.
8.10 
#3 - The Zarnecki Incursion
The Big Bang Theory Season 4 - Episode 19
Sheldon's World of Warcraft online game account is hacked and he is determined to find out who did it. Also Penny shares some girl talk with her friends about Leonard and his new girlfriend. When Howard discovers who hacked the account, the guys depart for a quest to Carlsbad, California where the hacker, Todd Zarnecki, lives in order to retrieve the stolen account, along with "enchanted weapons, gladiator armor, gold, and a battle ostrich, Glenn". Despite Sheldon carrying his Bat'leth with him they fail miserably. On the way back their car engine breaks down, and they're saved by Penny, who came to drive them home and upon hearing about their failure promises to show them "How we finish quests in Nebraska" and forces Zarnecki to give up kicking him below waist.
8.08 
#4 - The Gorilla Dissolution
The Big Bang Theory Season 7 - Episode 23
A bad day compels Penny to re-evaluate her choices -- including Leonard; Bernadette and Howard must care for Mrs. Wolowitz; Sheldon gives Raj advice on relationships.
8.05 
#5 - The Stag Convergence
The Big Bang Theory Season 5 - Episode 22
After the guys throw Howard a bachelor party, Bernadette reconsiders marrying him after learning about his sexual history.
8.05