Provo Craft first created the Cricut Personal Cutting machine - affectionately known as the "baby bug" a few years back. Then they improved it and introduced the Create - still cut the same size - 6 X 12" paper but added some features. Next came the Expression - lots more features, larger sizes 12 X 12 and 12 X 24. Two years ago they introduced the Imagine. That is actually an ink jet printer as well as a laser cutting machine. It uses the same cartridges, but you can actually print out the paper you want, and the layers for the design.
Lastly came the Expression 2. Cricut didn't want to limit their expansion of the product so this one is more like a computer. They will have the ability to be upgraded as Cricut adds features, by connecting it to your computer and downloading an upgrade. It doesn't have the same keypad overlays, uses a LED screen.
I have an E2, but haven't used it much. It is a whole new learning curve from the regular expression and being 63, I find the screen a little hard to read. Not sure I like this one as well, but I haven't spent a lot of time with it yet.
What does the Cricut do? It cuts paper with precision. No more buying sheets of alphabets, only using some of them and having to buy another whole set! TONS of design, word sayings like "Just married", or Happily Ever After, or Once Upon A time, .... it is endless. Cricut now has hundreds of cartridges out there.
Say you are a teacher, or want to make an invitation, or party favors, and want to cut out an apple - you need 20 of them - The cricut can cut them any size and as many as you need. It is an extremely versatile machine. You can cut vinyl with it and decorate your house (walls), make magnets with it, do a ga-zillion types of paper crafts with. Probably one of the most useful machines I have ever had.
The imagine is a little pricey and has been problematic. I would recommend as a new user to start with the Expression. You will absolutely LOVE cutting out words with this thing.
The next thing you will need is a XYRON. You put the letters into this, pull them out, and they then have adhesive on one side, turns them into stickers! You can get permanent and repositionable stick. XYRON comes in different sizes, take a look at them at Michaels, or Wal-Mart, or online.
Hope

this helps!