I don't see a need to jailbreak it unless you have something specific in mind. I had to jailbreak my iPad 1 because I use it as a digital picture tube in a vintage TV and wanted the iPad to go directly to the last running app when turned on (rather than the lock screen). That required a jailbreak.
But for your iPad, I'd recommend keeping it at iOS 7 if possible and using it as a dedicated arcade or pinball machine. The iCade cabinet or pinball dock would make it a fine retro game system.
You could also use it as a digital noteboard that is kept in the kitchen for quick notes, reminders. Maybe throw on a weather app or news feed as an "info center".
If none of that appeals to you, consider wiping it out and donating it to the local library, hospital, or nursing home.