Hi again.

Bored now a days and found passion again for Unsolved Mysteries.

Which segments are MUST see? I am interested in disappearances , kidnapping, murders etc.

Make a list :)

the Unsolved Mysteries Wiki would have alot of cases for you to look through

http://unsolvedmysteries.wikia.com/wiki/Unsolved_Mysteries_Wiki

I think some of the classic UM cases that everyone must see are:
Son of Sam (definitely!)
Tammy Lynn Leppert
Tallman Bunkbed
Charles Morgan/Don Devereux Mistake Hit
Orange Sock Murders
Mickey/Trudy Thompson
Tara Calico/Michael Henley
Amy Billig

I know I'm missing a ton but it would be a while if I sat here typing away!

The Wackers
The Circleville Letters
Son of Sam
Danny Casolaro/Don Devereux/Charles Morgan
Dan/DB Cooper
Wendy Camp/Shamrock Disappearances
Jeffrey MacDonald
Don Henry and Kevin Ives
Keith Reinhard and Tom Young
John and Linda Sohas
Doyle Wheeler
Dale Kerstetter
Chad Langford
Justin Burgwinkel
Monica Rizzo
Eric Tamiyasu

There are oh so many more. These are some that really pop for me.

Sammy Wheeler's murder, where it appears that none of the many accusatory and fingerpointing suspects were involved.

Danny and Kathy Freeman murders. Their son had been shot to death by police the previous year. At the time of the Freeman murders, their daughter Ashley and her friend Lauria Bible went missing (likely kidnapped, since they left behind a few hundred dollars in cash and other valuables) and were never seen again.

Kaitlyn Arquette's murder, tho the UM segment doesn't go into nearly as much detail as the book written by her mother, which really adds to the strange possibilities of what could have happened.

Larry Dickens murder by career criminal who went on the run.

Lisa Marie Kimmell's abduction and murder. Her mother's book goes into a lot more detail than the UM segment. Thankfully, the killer is behind bars.

Janice and Alyssa Owen's kidnapping and murders.

Thomas Hotard's murder and Audrey Moate's disappearance.

Dana Satterfield's murder.

Jill and Julie Hansen's arson murders with an unusual suspect and freak accident contributing to one girl's death.

Su Taraskiewicz's work related murder.

Thanks to all of you! :)