2 questions about Pwning

I had a really bad experience with Ziphone, and after several hours of biting my nails I was able to get my iPhone back working. Since then I've been gun shy when it comes to jailbreaking. I'm interested in jailbreaking again, but I've got two questions first. I tried to look up the answer to my second question, but searching for "un-pwn" turned up a lot of useless info.

1. What's the deal with boot neuter? I'm pretty sure my phone came with the 3.9 bootloader based on the serial number.

2. To go back to un-pwned firmware, all I have to do it restore in iTunes, right?

Thanks in advance and sorry for asking dumb questions, I just don't want to mess up my phone like Ziphone did before.