I am running Win10 on both a Dell Dimension 5100 and a Dell Latitude D610 laptop. Each case, the 'free' upgrade was refused due to varuous excuses, but downloading the .iso file and installing it all myself worked fine and everything works as it should even on these 'antique' machine! However that said, I opted for a Custom install and turned off all the privacy issues, but you can always turn them off later via 'Settings > Privacy'
For a browser, I use Pale Moon (a Firefox derivative) together with Adblock Latitude.