As a newbi, I will try to help as much as I can, my knowledge is very limited compared to most people here.
Also, I think my approach is one of the easiest and laziest.
First be sure that your server has a respectful power supply. I would recommend a 600W of a decent brand.
Second, I take it you will mine for a pool.
I use slush pool.
Register an account with them.
http://mining.bitcoin.cz/Have 2 workers, one for each videocard.
example, if your name is badass
you can name the workers
badass.r6770a
badass.r6770b
set a decent password.
On your server, I would use Guiminer
Download latest version
Run, point to slushpool
Put in user and pass of worker from slush pool
set extra flags, I use
-v -f0 -w128I think you can make tabs, I just open guiminer twice (4 times in my case)
Watch it mine.
I use TechPowerUp GPUZ to monitor my videocard temperatures
I also use Trixx to overclock my cards.
Don't burn your cards.
I can assure you there are far better way of mining and I am pretty sure guiminer is far from the best or fastest.
It works for me and it has not given me any headaches. The speed is respectable. It is brainless to make work and barely touches the Sempron CPU usage.
For some reason with my old mining rig, I used a command prompt miner (forgot which) and my cpu with 2 cards was at 100% (Running an Athlon II X2)
Good luck