Oatmeal Cookies

Sounds like the classic recipe off the side of a Quaker Oats box (if that's the proper term for a round container).

http://www.quakeroats.com/cooking-and-recipes/content/recipes/recipe-detail.aspx?recipeid=474

This version seems to be "updated" from my the one my mother makes, listing salt as optional. Don't leave out the salt. They're bland without it.

Thanks for the help! I tried a cup of softened butter and then just a little water (about 2 Tb) and they turned out perfect!

Don't use steel cut oats. For cookies, the recipes from your mother are Quaker Oats..either 'quick, or old fashion oats'...probably the quick if they came out super-dry. Steel cut, and quick oats are completely different products and can't be used interchangeably in family recipes for cookies.
I'm guessing Mom used the 'quick oat' product. Which was a 'given' in a recipe from the 60's-90's for cookie recipes. Today they usually specify the type of oat. as steel cut is common. But "Quick Oat" was the goto product of those decades for cookie recipes.

Hi, I think it's missing one cup of butter. I remember a recipe like this from my grandmother.

I would think a little or no milk and a lot of butter would be best. Oil would make them soft if that is what you are looking for, and shortening would make them crunchier but the flavor wouldn't match butter.