Right,

I have just sorted an old computer for my old man. He knows nothing about computers and now wants to get on the internet.

I was getting him to get broadband as we all know its better but the tight git says he cant afford it and will get dial up instead. I then remember that i did not bother to install the crappy 56k modem on his computer, Doh!!

I got him to take the modem out and tell me what its called, he tell me that it has P56K-536EP writen on it. I whack that into the search on this site and it gives me a modem driver to download, great i thought, ill download that burn it onto a cd and then post it to him, i know a little about computers so i thought it would be easy to talk him throught the installation.

Little did i know!!!

I was expecting to be able to click on a .exe file and bob's your uncle!!

having looked at the driver i have downloaded from here a little closer, it contains 5 folders, Nt4, Win9x, Win2k, WinMe & WinXP.
He has XP instaled so open that...
Then i get 4 more files..
Intels51 - security catalogue
Intels51 - Setup Information
IntelS51 - System File
MIGRATE.DLL - Application Extension

Please can someone tell me how to get this driver installed?

You must have either an EXE or INF file in order to install a driver for this modem. Since you didn't give file names in but the last line, I suggest you go to Intels website and download the correct driver.

http://downloadfinder.intel.com/scripts-df-external/filter_results.aspx?strTypes=all&ProductID=977&OSFullName=Windows*+XP+Professional&lang=eng&strOSs=44&submit=Go%21

eg:
Intels51 - security catalogue (Intels51 is not a file name, Intels51.cat would be a valid filename)
Intels51 - Setup Information (Intels51 is not a file name, Intels51.ini would be a valid filename)
IntelS51 - System File (IntelS51 is not a file name, IntelS51.sys would be a valid filename)
MIGRATE.DLL - Application Extension (MIGRATE.DLL is a valid filename)

If you are unable to see those extensions of a file name, then you need to go into Tools, Folder Options, View tab and change how Windows sees files.
Normally, a valid install set contains a SETUP.EXE (usually located in the root folder). Once launched, it should go to the proper os folder to pick the driver and how it's installed. Did you launch the setup file?