What exactly is a “hard reset” for my Samsung tablet? Also how do you get the thing open if you want to remove the battery? Is this possible.
A hard reset is when you reset your tablet to a state where there is nothing on the tablet except for the default apps and the operating system.
(source: I do it ever couple months to my brother's palm.)
What Susendeep describes above would be a "factory reset". A hard reset is most usually just a complete shutdown of the tablet, and then switching it back on. This can be done by long-pressing the power button on most devices.
Unless you really did mean a factory reset, of course. :)
More on what a hard reset means here: http://en.wikipedia.org/wiki/Hard_reboot#Hard_reboot (also known as a cold reboot)
Actually, there is a difference between restart (reboot) and reset. Soft reset is like a software reset, it is powering off then powering on the device. Hard reset is like a hardware reset, it resets the software on the device to factory defaults. Soft reboot is letting the device automatically shut down then start up again. Hard reboot is shutting down the device completely, then manually starting it up again.
Yup, exactly: When you long-press the power button on Android, this usually causes a forced shutdown. No matter what the device is doing, it will just turn off, BAM.
If you can pull the battery out, that's even better -- but if you can't, then this is often the same operation. Exact specifics may vary according to make and model, of course.
Actually, a hard reset is _not_ the same as a factory reset. A factory reset deletes all data & settings. A hard reset is simply the equivalent of switching the device off, and then on again.
Hard reset is a way to delete all the data present on the device and bring it to factory state i.e. a state in which the device was when purchased.
Assuming you have the Galaxy Tab, here is a video showing how to crack the tablet to replace the battery.
You can find instructions on how to perform a hard (aka factory) reset here.