Hello! I understand you're looking to disconnect your iPad device from the iWeb app while casting web videos to your TV. Let's get this sorted out together.

To disconnect your device when casting from the iWeb app, here’s a simple method you can try on your iPad (running iOS 17.7.2):

1. Open the iWeb app on your iPad.
2. Look for the Cast icon (usually looks like a screen or a rectangle with Wi-Fi waves in a corner).
3. Tap on the Cast icon to see the currently connected device.
4. Next to the device name, you might see a three-dot menu or an option that lets you manage the connection.
5. Tap that menu and select “Disconnect” or “Stop casting”.

If you don't see a direct disconnect button in the app, alternatively, you can:

- Open the Control Center on your iPad (swipe down from the top-right corner).
- Look for the Screen Mirroring or AirPlay option.
- Tap it and then select “Stop mirroring” or disconnect from the TV.

These steps usually disconnect your device from casting to the TV.

If that doesn't work or the options aren’t visible, could you please tell me if you are casting via Chromecast, AirPlay, or another device type? Also, have you tried any of these steps already? That will help me guide you better!