Well if you purchase from DAZ their installers are pretty good.You must remember to make sure that the files get installed into the content folder of DS.The Daz installers do the rest.Plus DO make sure to read the product page that comes at the end of the installing session because it will TELL you WHERE to find the product you just installed.I suggest making a written note about it in a small to be kept booklet, will help you find what you have installed.

Patience and perseverance are the way with DS(frankly it's easier than Poser any day).

You will find people and animals and the main millenium/daz characters/figures in the Figures section.Some under Daz people ,some under their own name,You will also find the basic part of any clothing in this section as well and there will be a separate folder for each characters morphing clothes.

Hair gets a little more complicated as some will be in DAZ hair but some will just be under their name in Figures and there may even be a DAZ hair file in Figures.

Hands contains hand poses.Faces contains face poses.

Then in poses you get all the morphs for all the characters.IE how to change shapes,how to alter faces,make a character fatter,muscular.These are INJected or plused onto a character.You can also remove a morp if you want to by clicking on a minus sign.

Also in poses you get the materials IE the fun part of setting up your characters.Here you will find hair colour,changing hair styles.You will find the different texture choices for clothing,and the body textures for you chosen character usually known as 'maps'.These will include skin texture,colour,make-up and eye colour.
Also here you get to pose your character in the position you like using ready made pose packages

In Props should be the objects that you will assign to character for their use.IE staffs,swords,guns,food,furniture.

Camera contains the camera postions for certain scenes that you can purchase.

Lighting contains the lighting that comes with those scenes as a ready made aid to save you setting up your own(the most complicated part of setting up a scene in my book and I'm pleased when I'm provided with one).

Don't forget that DS does have a pretty forgiving undo tab unlike Poser where you only get to undo once.

Now I hope I have been helpful.