The Skywalker-2 website says:
This hardware/software/firmware does NOT do any decryption. It's for clear/unencrypted signal ONLY.
On Lyngsat, light green HD channels saying HD/clear are the ones you can view legally for free.
You won't be able to receive anything that says DVB-S2 with a 30 inch dish. To get that, you need a much bigger dish.
A 30 inch dish is the smallest practical size for the most part. (IMO) However some people have luck getting stuff with smaller dishes.
I think the best overall size to begin with is a 36 inch dish. But as with a lot of things, BIGGER IS BETTER.
For most free to air stuff the LNBF you want is linear polarization. (V, H) The other kind is circular. (R, L)
An LNBF with a lower Noise Factor, NF is usually better.
If your budget supports it, you may want a QPH-031 LNBF. It does circular and linear polarization. Also, a motor to point the dish is good idea.
EDIT - One more thing:
Not sure if I need to explain this, but: From Memphis it's only possible to see satellites located at 25W through 155W approximately. (trees, buildings and other obstructions notwithstanding)