Mini 1.
Before I get started is there anything I need to know about Erase All Contents and Settings when it comes to keeping ios 7 on Mini?
It won't force me to upgrade at the end?
Any contacts, personal info, bookmarks, email accounts, photos etc can be backed up to iCloud or iTunes whichever you prefer. Erase all contents will do exactly what it says....1...2...3...poof goes your data and everything else. There's no going back.
Once the iPad reboots you can download everything from iCloud or do a restore from iTunes. If you do a restore via iTunes you will probably see a prompt to update to iOS 8. You can cancel and check the box, "don't ask again".
Eventually you will be prompted to update OTA because iOS 7 phones home a lot just like Android, looking for OS updates.