that's basically the same system that is running http://thirtythreeandathird.net
(mine) which also has some other domains on http as well as dns, smtp and a number of other services including some php. it runs rh7.1 on two small hard disks.
you should be fine as long as you are conservative abuot what you install.
"3) What is gnome?" do you really think that you couldn't find out yourself???