haha... i built a machine last year with win98, win2000 and redhat 7.0 as well. it took a few days, but i finally got it... well, almost.
you need to check the
Redhat compatibility list to see if your network card is supported. if not, i do not know how to create a driver for it. my Linksys EtherFast card was not supported when i built the machine so i did not bother with it. i just got Redhat 7.1 yesterday, and i am hoping it will support my card out of the box.
a friend of mine has the same card i have, but has not been able to get it to work on 7.0 yet. be bought a cheap $9.00 card and 7.0 recognized it on the first boot. i cannot remember the brand name at the moment.
as for your verticle / horizontal scan rate... you can change that through KDE. i chose mine during setup and haven't had any problems with it. i do not have my linux machine here so i cannot tell you where to go in KDE yet. i will check when i get home and let you know. if you find the monitor configuration tool, just find a monitor that is the same brand as yours (i.e. sony) and the same size (17", 19") and select it. only one of my 3 monitors were listed specifically, but all 3 work fine.
i am new to linux, but i hope this helps.