Skills and achievements - This is where you talk about the foreign languages you speak and the IT packages you can competently use. The key skills that you list should be relevant to the job. Don't exaggerate your abilities, as you'll need to back up your claims at interview. If you've got lots of job-specific skills you should do a skills-based CV.
Interests - 'Socialising', 'going to the cinema' and 'reading' aren't going to catch a recruiters attention. However, relevant interests can provide a more complete picture of who you are, as well as giving you something to talk about at interview. Examples include writing your own blog or community newsletters if you want to be a journalist, being part of a drama group if you're looking to get into sales and your involvement in climate change activism if you'd like an environmental job. If you don't have any relevant hobbies or interests leave this section out.
References - You don't need to provide the names of referees at this stage. You can say 'references available upon request' but most employers would assume this to be the case so if you're stuck for space you can leave this out.
For more help and advice on how to write a CV and to find CV templates, see example CVs.