I used to have a bunch of those and I sold them.

I have a number of spools that are wooden...still lots of thread on them. But I think they are too old to sew with. I instead use them for basting and then save the spools.
If you tug on a section, and it breaks easily, I would not use it.
Not familiar with the other items...

I'd say display in a jar like Dal Lady says. They're collectibles to lots of quilters/seamstresses.

My mom used to get thread for embroidery on paper bobbin type holders...That was a long time ago...

The iron on transfers for embroidery will last for a long time. I understand people are paying big bucks (in my opinion) for some of the original 29 cent ones. I still have a supply of iron-on transfer patterns that cost 10 to 29 cents each.

Wooden spools haven't been sold for at least 30 years. According to thread experts, thread has a shelf life. I'm not so sure. You can make up your own mind.

Lucky GAL! I have some of your Thread. I WILL NOT SAY ALL OF IT, but they are better than today, you just have to check it, Some will made out of 100% cotton, some can be 100% Silk or Raw Silk, or Mixed with other fiber or Material that they make the thread. You can use for BASTING and/or Embroidery, decoration for applique, so I will say, if you are a quilter and also crafter, I will hold on to it, beside Fabric, even thread are expensive TODAY! You can use the Transfer for labels

I think the spools of thread may have been samples for salesman? I have several and display them. If I had more I'd display them in a glass jar etc. Keep them!!!

like so many others, I have many with and without thread in mason jars in my sewing room...I have some of the old transfers and patterns with my vintage machine and other vintage notions that I have collected and accumulated over the years.

I need silk thread for my entirely silk friendship quilt. I've been gathering items for over 20 years but it is so hard to find silk fabric much less silk thread! PM me if you are interested in some kind of swap. I am not interested in the spools, you should probably keep them. Thanks.
djmat