Anything important from Jagex regarding your account will be sent to you from them within your in-game inbox. Any game updates you can navigate from directly within the official website. Any emails you receive regarding either of these I avoid entirely. Though a small few could be deemed legitimate, it's mostly from phishers hoping you open the email and click on the re-directed link. Granted, the link can be highlighted over for authenticity, it's still an un-needed risk.
Another common one as of late are the many Discord servers being thrown out on the social wellness of the community. Without proper settings from the program, you could automatically download any unknown file a stranger sent over.