Configuring a Kernel (doubts)

[Paredes Sánchez Martín A.]

Hi:

When installing FreeBSD, in the "Kernel Configuration Menu" I select the
full-screen visual mode because I want to disable all the SCSI
controllers (only have IDE drives) and the PC-card controller (it is not
a lap top). 

am I building a new kernel?, so the next reboot I have the same
configuration.

What files are modified? Since I don't see this changes reflected in
/sys/i386/conf/GENERIC

As you can see, I want a personalized kernel, also want this PC to have
X-Windows and the ability to be upgraded.

The question is:

Do I need to install kernel sources or full sources?

maps