I wrote a basic shopping list for a RPi
http://www.raspberrypi.org/phpBB3/viewt ... 0&p=453257
Get lots of 4GB SDCards and you can have various flavours of operating system available to run with a card switch and reboot.
XMBC works with my daughter's iPhone, so should work with your iPad. I'm using the OpenELEC version of XMBC.
My RPi normally sits under the TV running Raspbian. I've got a hardware breakout board & breadboard attached with a few resistors and LEDs (on pins 18, 27 & 22) and a switch (pin 17). So I can run GPIO experiments without having to fiddle with any H/W.
Anyone who posts a RTFM or LMGTFY in the Beginner's Forum should be cast into the sin bin for a week by the moderators. We were all beginners once. Although doing some searches before posting can reveal the answer. Using Google with "foo bar site:raspberrypi.org" will restrict its searches to the forum. BUT, that assumes you know the words to search for.