How to transfer whole linux box

[Alok Pandey <alok rhct gmail com>]

Hi Troubleshooters,
I am almost confuse to how to make start. I want to shift my linux 
server to a branded new machine as the old one was rented and now i have 
my own desktop.
I am really confuse how to proceed as
-- will i first install linux on new machine and then step by step 
,reconfigure all the services i.e (local dns, dhcp, nis, wikki, 
bugzilla, plone ,etc) ( if it's the right way , i will really be a big 
pain :'( ) or;
-- I can took off the hard drive from the older one and attached it to 
new machine (but their will be lot of compatibility issue, ) or,
-- I can install linux on new machine and COPY whole "/" from old one .


I hope the above info will be sufficient for you to understand my problem.
Plz show me a light ,as all around is dark

Thanks and regards to every one
alok (newbie)