For your budget, I agree that a Brother PE770 or a Designio 820 will all be an easy machine to learn on. The 820 is just a PE770 in a different color and it comes with more hoops and other stuff to get you started. There's also the Janome MC200E, but it's largest hoop is 5.5" square where the Brothers have a 5x7" hoop. The large hoop Chasing Hawk talked about is a special hoop for doing split designs, the machine will not just stitch out a bigger design than 5x7. Brother makes these entry level machines well, they're good machines, but I'll tell you in my experience with 5 embroidery machines(2 Brother and 3 Janome) that the Janome machines are actually more user friendly. With all the major brands having their new lineups coming out if you wait a few weeks you'll be able to get a good used machine, saving a lot over buying new. Either a trade in from a dealer or as a private sale from someone who wants a bigger machine. I bought 3 of my machines used and haven't had a single problem with them.
Cari