As MiiHere said - it depends on what you want to delete.
Apps - Go to Settings, then Application Manager. You 'll see a list of all the apps on the tablet. The default list that comes up is "Downloaded" - those that you have added, and that you can uninstall. Click each app you no longer want, and choose Uninstall from the screen that comes up.
Once you've cleared those, you can scroll over to ALL apps and see what is left that is pre-installed on the tablet, by the manufacturer or by Verizon. Those that don't have an "Uninstall" option will have a "Disable" and "Force stop"; you can't delete them but you can disable them.
Photos, Music, other media - You can move most of these to an SD card, or use an app like ES File Explorer to find them on the tablet and delete them.
If there is something else you are trying to delete and it's not working, post back and tell us what it is you weant to delete; we'll help you figure out how to get it done, if it's possible.