The last couple of days has seen some problems with the RuneScape website. This problem is JUST the website, so the worlds appear to be safe. However, the RuneScape client directs you towards the main website. You can, however, bypass the main website when using the client:
1. Go to the folder C:\Users\YOUR NAME\jagexcache\jagexlauncher\runescape
2. Open the file runescape.prm (right click) with any text editor, such as Notepad or Word.
3. You should see this:
4. In the third line, change the "www" to "world1" (or any other world number, as long as this world actually exists).
5. It should now look like this:
6. Save the file.
7. Open the client. It should now load, bypassing the main website, immediately loading the server of the world you specified.
You can change this back at any given time.