I've started up Don't starve and went into the settings and made it fullscreen, but that minimized it. I tried deleting local game files and then re-installing it but that still won't fix it.
Have a look at your
settings.ini file. You can find it in your user directory. For instance, mine is at:
If you can't find any settings there to fix the minimization, you might try just deleting the settings.ini file to see if the game will re-create it. (Don't permanently delete it; just send it to the Recycle Bin, so you can get it back if this experiment doesn't work.)