Top Questions to Ask a Client Before Creating A Website

What is the Client Business?
What do you want your site to accomplish?
What are the top 3 frustrations with your current website?
What do your current competitors’ websites have that you wish to have?
What about the website you like that you would like incorporated into your website?
What types of things do you see on other websites that you really like and hate?
Where is your website hosted? Do you have full access?
Once the website is complete, how will you be managing website upkeep?
Do you have a URL you plan to use?
Does your current web host meet all your new website’s needs (space, bandwidth, databases, etc.)?

FEATURES: What do you need for your website?

Blog
RSS
Forum
Forms with emails
E-Commerce shopping cart
Newsletter signup
Auto responders
Advertising positions

Does your site need to be responsive?
Do you have any specific mobile requirements?
Do you need password protected areas?
How many web forms does your new site need? What is the purpose of each?
Do you need social sharing features built in (tweet, like, etc.)?

Do you have current style guide or any other materials that the website needs to match with in some way? (brochures, press materials, etc.)?
Do you have specific color scheme?
Do you need favicon created?
Will video or audio be part of the new website?
Do you have any specific images that will need to be used? Do you have full rights to them?

What information must be on the homepage?
What features, sections or information do you want emphasized on the site?'
Will different sections of your site require different designs, layouts or coloring?
Do you need an internal site search feature?
Do you want contact phone numbers prominently displayed?
What's the total amount of pages involved?

Is there anything else that needs to be added on the website that wasn't covered on this list?

Sources: http://marketingland.com/100-questions-you-must-ask-when-developing-web-site-86342
http://blog.web123partners.com.au/blog/the-10-questions-you-must-ask-your-client-before-designing-their-website.aspx
http://www.albasoftgroup.com/en/Blog/11-questions-you-should-ask-potential-client-for-web-design