This is where the EFF’s HTTPS Everywhere extension comes in handy. It will make these websites default to HTTPS, and will alert you if you try and access a site that isn’t HTTPS. It’s free and you can install it here.
If you just want a secure way to browse the web without ISPs being able to easily snoop on you and sell your data, Opera is a great start. Let’s install and configure it real quick. This takes less than 5 minutes.