Thank you for the details of your setup.
The first thing I would change is to uninstall Norton and replace it with a different AV system. I would suggest the free Avast, Basic File, Email and Network scanner. There are paid versions should you wish more protection. However, I've been running Avast for years on basic with no noticeable slowdown or problems. There is also Avira but this was bought by Avast recently so you're basically paying for the same thing. Kaspersky is also an excellent AV system but not as user-friendly.
The size of your doogiePIM databases are really quite small. My daily database is 518MB and my wife has a cooking database that is equally well over that. My development KB is touching 3.6GB now. That contains mainly Documents with a large amount of text and some graphics. Therefore, I can only conclude your database is not the problem.
The doosi file is an index used by the Global Database Search system. This enables you to perform a fast search of your database content. This index can be recreated at any time and can be much larger than your main database. This is not a problem area and doesn't need to be backed up if you're happy to rebuild the index.
Backups should be made each day. Your doo file is the most important part of your data. There is a quick backup command in the File menu "Backup Database". This performs a one-click backup copy of your database you can store on a different disk. The backup file is encoded with the date and time of last save and when it was created so you know which backup is which. Place the backup command icon on your main toolbar and use it each day.
You can load a backup file into doogiePIM and export a single Document to a don file. You could then import that don file back into your main database, should you wish an easier way than copy/paste.
Your laptop is a very good one. Lots of good reviews and is certainly a good choice for running doogiePIM.
I really don't have much more to say other than to make regular backups and I'll see if I can code in some further protection against saving a blank document when there was one there a moment ago. Perhaps a new user option in the settings "Don't save empty documents". This would protect against hitting Ctrl+A then Delete or Space, then if the AutoSave timer just kicks in, you get a blank document.
I hope this stirs some positive vibe to the matter and have a great weekend.