Ok this is probably a really stupid and obvious question, but I can't figure it out. I have read the instruction book cover to cover, tried clicking everywhere in game like a mad man, but I cannot figure out how to give Ian weapons/armor and tell him to use that one. How is this done? Secret button I'm missing somewhere?

Fallout 1 doesn't allow you to equip NPC's with any armour/weapons. They can only use the default equipment.
In Fallout 2 you have to start a conversation with an NPC to find a menu that allow you to change equipment.
P.S. there are no stupid questions, only stupid answers ;)

Dear lord. I thought I was missing something and getting frustrated lol. Thanks! So if I tell Ian to use his best weapon, he will use his gun. Will he run out of bullets? Do I just open the barter window to give him more? Wish I could tell him to use the knife and not waste ammo.

oO Just hold the right mousebutton clicked over one char, choose the backpack-symbol and choose a weapon to give it to one of your NPC's. They will use it.
This doesn't work with armors, but with weapons it works fine.

Ok, so if this statement is correct (and thank you), if Ian now has the knife and the gun in his possession, how can I direct him to use the appropriate weapon?

Ok that clears it up. Thanks for all your help Real, much appreciated.

Oh, sorry. My mistake. I guess that was a stupid answer.

Know this is an old post, but this is the first result that shows on Google and there's a lot of inaccuracies in the replies. And with the free Fallout 1 giveaway here, a lot of people are probably interested in this.

If you talk to NPCs, they'll tell you what kinds of weapons they can use. All you have to do is trade or steal/plant it on them and give them the right ammo, then just tell them to equip their best weapon. The only problem with this is it that it goes by what the game considers "best" and doesn't allow you to manually choose.

One way you can force them to use another weapon is to trade or steal all the ammo for the gun they're using, and give them ammo only for the gun you want them to use.

NPCs will also switch weapons sometimes on their own, so if you don't want them doing that, wait until they equip the weapon you want them to use, then trade or steal their other weapons or the ammo for those weapons.

They'll also use any stimpacks or super stimpacks you give them, but they will not equip armors.

There's also mods for this, if the armor problem (or the problem of not being able to leave your dog behind) is a dealbreaker.

Yes, there are mods for NPC Armor switching but honestly - they are bugged and may corrupt your games. Well.. at least when you try to use FIXT package. Everytime i started playing with this add-on, my game gone crazy when saving after time.

Does anybody use single NPC armor addone without troubles?