Beware that Video editing/encoding is similar to making VHS tape copies... a slight loss in quality for every re-encode (typical digital movies are not encoded losslessly). So if you make video edits, best to work with original digital copy (ie, first time you encode from analog). Adding title and others later is ok, but will typically mean a re-encode.
Though a lot more complicated (and probably not worth it...), this re-encode reason is why some folks, when encoding for analog try to make, things like an intro title/slide, sub-titles, etc part of the original compositing/encoding. But, if you can't get it all in with OBS Studio, and getting exact timing right, etc... is why I intend to encode at a higher quality than needed (so the loss in quality won't be (as) noticeable, then video edit once afterwards.
What you don't want to do, if at all practical, is encode/save video. Make an edit (editor of choice... though higher-end editors with more powerful computers will, on average, have lower quality loss... though it really does depend), save (re-encode), later make another edit, save (re-encode), etc. Some video editors (like photo editors) will let you make 'adjustments, but save those in a 'side' file. You can make as many of these as you want. When you want in Preview window, you will see all of those edits 'combined'. But you one Output (Encode) when done. And if you realize you need to fix an edit, or do more, you are still working with the original video file.
Also
- I recommend testing burning to DVD and seeing if you like the results (original was 4.7GB). You are limited in file size, and that will impact perceived video quality. Movie studios have REALLY high-end systems that can more highly compress the video and still make it look good to fit on a DVD. You may need to break the videos up into smaller chunks so they fit on a DVD at a quality you like, or you may end up instead posting videos to a private online share (Google Drive, OneDrive, ... lots of options), or getting cheap 1TB flash drives (or whatever size makes sense) and sharing videos on that. I do agree to archiving to a longer-term media than flash drives, cloud storage, etc. Just realize that finding a DVD player at a home is getting less and less common. just a thought