So i am working on a restored nipton mod and i was trying to get a some of those dead npc's out (im new to modding btw) i went to the npc menu and deleted some dead wastelanders but i then realized i needed to delete just the dead nipton wastelanders so long story short my game is crashing and i need to figure out how to undelte (oh the irony) some of those npc's.

Go into the GECK, and on the same screen in which you select the mod to load there should be a button that says something like "Details" or "Options". Click that, and it will bring up a window listing all the changes made by the highlighted mod. Find the line that mentions the NPCs you deleted, and press the Delete key. This will put a line next to it indicating that this change will not be loaded when you load up the mod in the GECK. Then just load the mod and re-save it.

Thanks i was able to fix it but now im still stuck with these niptondeadguys who wont delete, i go into geck and take them out but when i load the game they are still there even though all the other changes i made still are.

Have you tried disabling them?

I went in the geck clicked on them and hit delete.... isnt that disabilling

Another thing you can do is if you have FNVEdit you can load the mod in question and removed the edited records from the mod it self. This, from my understanding, will basically have the mod appear as though the edits never happened.