Unneeded Services

Hi:

When I installed RH 7.1 I selected the medium security setting. With
this recent debacle with sendmail though I was curious what other
services were running.

I logged in as root and ran ntsysv. I found the following that in my
thinking might pose a problem or I just do not need it. I plan on
offering no services but merely want to do the boring stuff like email
and web browsing. I do want to set NAT for the Win box, but that is
all at the present.

Do I need the following services?:

apmd
netfs
nfslock
portmap

BTW, how do I check/uncheck these in the ntsysv GUI?

Mike