Weird, you meet the recommended requirements for RAM, don't know why it would be telling you that.
Chrome can be a bit of a RAM hog, did you take that screenshot without Chrome open? How recently had you closed it? I don't think it's unusual for it to stay in memory for a bit. If you actually start needing that memory for something else windows should flush stuff from memory or move it to the pagefile as needed.
Are you having performance issues in WD2?