I have a mid-2010 iMac that I haven't used for a while. I wiped the disk and installed High Sierra (10.13.6). I don't remember the previous release of MacOS it was running with. It has a 3.2GHz i3, 1T HDD and 12G of RAM.
It's incredibly sluggish, clicking or typing will often result in the spinning wheel for a few seconds before anything happens. I've installed nothing on it beyond what High Sierra does by default.
My intention for this Mac is to use is for web browsing, writing, watching videos and music creation (with Garageband or other DAW).I have no intention of changing the HDD to an SSD - I don't think it's worth the cost and I have 2019 iMac that I have access to. This is just a secondary computer I'd like to have in my house.
Would an older release of MacOS fix this sluggishness? What release of MacOS would you recommend?