Yep, Nell had plenty of addictions, from drugs to food. I, too, heard that she did blow on the set. It makes sense because on many of the episodes, she was very hyper (remember the one where she picked up Telma Hopkins and bodyslammed her onto the couch?). For a big girl, she was really light on her feet, though. She was always good at physical comedy.
As for getting that "tingling" feeling when seeing a guy on TV, Jonathan Silverman used to do that for me when he was on this show. He was kind of hot back then.
Some of the more memorable episodes for me were:
when the Chief died (actor Dolph Sweet passed away in real life)
when Katie had an IUD scare
when Whitney Houston guest starred as one of Katie's friends and they sang in a pop group
when the Pointer Sisters guest starred as Nell's three backstabbing old friends
when Julie and Jonathan announced they were pregnant
when Samantha thought she was pregnant just from kissing a boy
when Jonathan accidentally shot Nell in the foot
when Samantha, Joey and Nell went back to Nell's hometown and Sam dressed Joey in blackface, angering Nell
when Nell held the PORKO fat club at the house, and later in the episode they all ended up getting stuck in an elevator
When the tall, ditzy Angie suckered Nell into selling the Amaz-o-Vac vacuum cleaner
when the chief's racist sister wanted custody of the girls because she didn't like the idea of a black woman raising them
when Nell and the chief went on crash diets at the same time and ended up eating everything in the kitchen
Anything involving the kookie Simpson was funny as well.
Also any episode where Nell sang was a treat. I still loved the show when they left the Glenlawn, California setting and uprooted to New York City. The only ones to stay on board were Nell, Telma and Joey, and new cast members included Andrew Lawrence, Rosie O'Donnell, Rosetta Lenoire and Paul Sand.