The Hulu application will appear under the TV/Video Services category in the XMB (cross media bar).
Before you can use the Hulu app on your PS3, you must ensure you are logged into the PlayStation Network. This can be done by heading to the PlayStation Network Icon on the main menu (XMB), choosing Sign In and entering the e-mail address and password associated with your PSN account.
Once you are logged into the PSN, head to the Hulu application. There are two ways you can log in to the Hulu application on your PS3.
For new subscribers, first launch the Hulu app. You will have the ability to sign up for Hulu directly from within the Hulu app on PlayStation 3. By signing up for Hulu on your PlayStation 3, you will be billed each month through your payment source. For more information about Hulu billing, please visit here.
Closed Captioning can be enabled on videos that have it available. During playback, pull up the playback menu by pressing Up on the D-pad. Press Up again, then toggle over to Captions: Off and Press X to enable.
You can also turn on captions for every video when available in your settings on the PlayStation 3. To do so, navigate to Account from the main page of the Hulu application. From there, tap X to open up the settings. You should see the Captions settings at the top left.
For troubleshooting help with your PlayStation 3, please visit this help article.