I could show you an article from a while back to do what you wanthttps://www.michaelhartzell.com/Blog/bid/17520/List-of-19-Presentation-Software-and-Tools-Create-Produce-Present
The list includes the good and the bad.
But I think the simplest and most straightforward way is to look at tools and skills you already have.
Windows Movie Maker - Free
If you can wield MS PowerPoint well, you can click on "create a video" inside the tool. In order for it to work well, you will include automated slide changes.
You can add narration as well.
You mentioned "Screen Shots" - the simplest, easiest tool to get this is Jing by TechSmith. It's free.
You can add these to your PowerPoint.
What will happen when you download Jing - You will see the option to record a video as well. :) Which is very doable.
But recording a live video that works well is not as easy as it appears. There are subtle differences when recording a live screen for a presentation.
- A narrated slide deck forces us to go point by point.
Then - if you like Jing, you will graduate to Snagit by Techsmith.
I don't go a day without using Snagit. About $50
It is an essential tool.
Window Movie Maker is free and already available. It is an option to do some editing to the video - where there are pauses or errors.
But then... once you like Jing and Snagit, you will say I want something better than Microsoft Movie Maker - and you will happily pay for Camtasia from TechSmith. About $300
I guess you see a theme by now.
Skip to the end - It does it all.
But first, use Jing to take the idea around the track.,
(Once you get done with the videos, you will want to host them. I don't recommend TechSmith Screencast for professional hosting - ok for internal, but not customers)
Then you will add Wistia to your inventory. (A long list of reasons why)
I use them all - these are the best for entrepreneurs.