How do I include - and ' in this regular expressions?

Hyphen is already included (twice), you can add the apostrophe by just editing it into the character class:

/^[a-zA-Z-\-\ ']+$/

You can rewrite it to look like this, so that there's no need to escape the hyphen and it's only included once:

/^[a-zA-Z '-]+$/

Example: http://jsfiddle.net/a4vGA/