DVD's

May I suggest an alternative approach? A digital slideshow picture frame may be a better approach perhaps.

https://www.amazon.com/slideshow-picture-frame/s?k=slideshow+picture+frame

Create your images, slides with text, sounds, short videos - compile a slideshow with these, and upload (usb) to the digital picture frame. Digital picture frames are quite affordable now, and it may be an easier and more approachable (and fun) way to present your shared memories. As long as it is hooked to an outlet, it will continue to play, and your friend can enjoy these at any time.

Also easy to update with new memories.

You obviously need a DVD disc burner.   Many/most newer computers don't have DVD drives.  And not all DVD drives on older computers can burn discs.

A more important question is how you plan for the DVD to be played back.   If you want  a true DVD that can play on a set-top box DVD player, then you need some specialized software to create the disc.  However, if you intend for the memory disc to be played on a computer, there are other options to consider.  And, in this day and age, if you are talking about viewing the photos on a computer, then a USB thumb drive would be a better option and you could create a slideshow, using Photoshop Elements.

1. Put all your photos/ videos in the same folder- in a location you can find easily. 

Do you have premiere elements?  If not, Do you have any software that can burn dvd's?
If not, I have a link to a simple program that is almost 10 years old, but quite capable.