Closed source on Linux and BSD?

An anonymous reader writes: I want to start (very small) software/hardware business.
The code in question will be a closed source.
I won't modify or use any GPL code or any 3-d party sources.
It will be my own handwritten C/C++ code from start to finish.
I am planning to sell embedded-like boxes with an OS (Linux or BSD) and this code.
I am more familiar with Linux but I am scared a little bit of Linux licensing (and quite a bit of Linux fanboism: I personally got "go to hell with your @#$ closed code" slur on ./).

My questions:
1. Can I do it with Linux today (GPL2) and tomorrow (GPL3)?

2. Can I statically link the code with Linux libraries? (My own experience shows that dynamic linking is too much to bear. Your mileage may vary)

3. Can I obfuscate my code (e.g. encode it)?

4. Could I be forced to publish this code by some 3-d party?

5. Am I correct that programming in and selling BSD-based box won't have any above problems?

As you can see, I am not a GPL guru and not a software freedom fighter.
I just want to do my job and make some living.