New Linux Server and need hardware advice

Ok... here's the deal.

I need to look into setting up and purchasing some new hardware. This is going to be for a Linux server, fedora Core (I guess..... it will be my first project of this nature. Anyone care to help ?) I am setting up a (thin?) client -server environment, mostly for the tons of free educational games and software for kids. (Anyone familiar with HOSEF and their project ? )

Also... years ago I remember a friend setting up a Linux server to be the file server for a windows network. Anyone familiar with this ? I am interested in having central file storage, backing up files, then even migrating the backups over to a remote machine (across the internet or network)

Other than my laptop computer purchased 2 years ago, I have not actually purchased a computer in about 7 years. (the only reason I picked my laptop other than it being cheap, was the neat button to turn off the built in mouse pad, otherwise I am constantly tapping it and doing things accidentally)

Since it has been so long since I really paid any attention to the hardware, I am looking at some of the names of processors and such, and realize none of it means anything to me any more. They are not very descriptive, or I don't understand what they are describing.

I am looking at this site to get a clue of pricing :
http://www.pricewatch.com/

I would prefer to deal locally, but would also like to know what I am looking at before I start talking.

Does anyone have links they can provide that visually shows the various CPU's scale of performance for speed ? How about some decent locally owned computer stores to get the hardware.

Also.. any of you Linux guru's that care to help out, I would really appreciate it.
THANKS !