It is indeed "Hollywierded" up, but it's not too bad. However...
In Jericho: "Fallout" only happens during rainstorms, and is only dangerous for a few hours. If you don't have underground shelter, plastic sheets on the windows will do in a pinch.
In reality: You need to shelter for a minimum of two weeks for the worst isotopes to burn off, and even then, it's minimum exposure when absolutely necessary. More like a month. Plastic sheets can help keep things "clean" of fallout dust, but the gamma and neutron radiation coming off that fallout will go through it like a hot knife through butter. Even a basment is marginal protection because of the exposed top of the foundation, and the wooden "roof" of the first floor is too thin.
The best protection is a few feet of dirt, rock, or concrete.
The redeeming factor: At least Jericho mentioned fallout and treated it as a real concern, even if the on-screen execution was poor.
In Jericho: Tincture of Iodine cures radiation sickness.
In reality: Tincture of Iodine is POISONOUS. Ingesting anything other than a few drops used to disinfect water is a "bad thing". Many people, often children, died during the Chernobyl disaster trying this. You need KI Potassium Iodide pills. And even then it only protects your thyroid by "filling you up" with "good" iodine, which prevents the uptake of radioactive Iodine 131 in the fallout. All the other fallout isotopes are still deadly. Even then radioactive iodine outside your body will still be irradiating you...
The redeeming factor: At least they knew something about the Iodine. However, it has the potential to poison however many millions of sheeple who's only knowledge of iodine and nuclear war/disaster was what they just saw on TV...
The way they treated EMP wasn't too bad. It takes large bombs detonated at high altitude to create widespread EMP effects. Groundbursts minimize it much closer to the line-of-sight horizon, the ground absorbs the rest. Even in a "worst case" EMP scenario where it's detonated to maximize the effects, electronics connected to some kind of antenna, long pieces of metal like pipes, power lines or fencing are the most affected, because the antenna collects the EMP and creates voltages in the line the longer the antenna is.
Small rural power grids could posibly protect themselves with breakers, surge strips on computers, breakers and fuses inside appliances, and stand alone items like cars might survive better than people would initialy think within a few hundred miles of a groundburst.
Although the local EMP from the Atlanta blast would have cut off the poor kid's mom from leaving that phone message the second it detonated. The line would have gone dead instantaneously.
If the show dosen't get any more "soap opera-y" than it is now, and the main drama is confined to the survival chalenges. I'll keep watching.
Next week, the RADIATION SICKNESS HORDES OF DENVER ARE COMING!