You mean www.freeridegames.com? That site is Mcafee secured so i assume if you downloaded a game you now get nag ads. You can ask them how I assume they have contact details
To block depends if they have installed a program on your PC maybe restore back to before you went there. Try deleting the program in safe mode those are some ways.
The 'Free Ride Games' player should be disabled before starting the uninstall process. To disable
the 'Free Ride Games' player, simply right click on the 'Free Ride Games' icon, then click the "Exit" button.
1. Click on windows 'Start' Button -> Settings -> Control Panel.
2. Double-click on Add or Remove Programs.
3. Select "Free Ride Games player" and press on the remove button.
4. Select the "Remove All option" to delete all Free Ride Games’ games and the 'Free Ride Games' player from your computer.
5. If you get a message to close all web pages.
Please close all 'Free Ride Games' web pages and press the "Retry" button.
6. In rare cases another message will pop up asking you to close the 'Free Ride Games' player.
If you encountered this message, please follow the instructions below:
1. Open "Task manager".
2. Select the processes tab.
3. Search for "GPlayer.exe" process.
4. Click it, and click on the "End Task" button.