for everything dealing with computers.
avoid thecableclub.com...i ordered from them 3 weeks ago and haven't recieved anything
these boards look interesting and generally go for ~$40. that integrated adaptec u160 controller is $150+ if you buy it seprately. the board only takes pc133 ram and up to 1.4ghz athlon processors though. both are very cheap. the 160 controller is useless to most people, but it would be nice if there were some p4/Athlon XP boards that came with it and supported faster ram.
1.8ghz is a good processor speed. its questionable if processors faster then that make a noticable difference unless your a heavy gamer. and in a few months AMD and Intel will release 64bit processors making everything out now obsolete, so don't invest too much yet
get a 7200 rpm HD. preferably with an 8mb cache, but thats not as important. some people are determined to keep their HDs forever and are suprised when they eventually fail/crash and *everything they had* is wiped out. i generally replace mine about every 18 months so that doesn't happen, which also means that i don't need the absolute biggest drives because i'll have another one by the time the space is needed.
getting a big monitor,good keyboard and mouse is pretty important because thats how you interface with the computer
if at all possible, get high speed internet.