I'm assuming you mean the brand 'Mustek' for the scanner. If your dad can get complete Compaqs cheap why not go that route?
If you must build, any Super 7 board from Asus, EPoX, AOpen, Shuttle will be fine. I've used the EPoX MVP3G2 and GiGaByte GA-5AX before and found them both to be satisifactory.
-=S_Klass=- I tweak... therefore I am.
Get an ABIT VA6 mobo- superstable,although not the greatest performer - check out www.hardocp.com for a review of it.
A celeron or celeron][ would be your best bet. They simply can't be beat for price/performance. I wouldn't use K6-x's, cellies are way better.
Get some decent PC100 or PC133 ram, try to stay away from the cheapest stuff. 64Mb is the ABSOLUTE MINIMUM! Try to get 96 or 128mb if you can afford it (It's better to have 96mb decent ram than a 128mb stick of crap)
An IBM harddrive would be the best, but if the system isn't going to be overclocked get a 5400 rpm WD, they're cheap . Check the cooling though, my 7200rpm WD died on me because of heat
For the graphics card I'd suggest that you check out pricing on Voodoo3's. They're decent cards contrary to what a lot of people say. If you can get a GOOD TNT2 card for the same price then I'd suggest you go with the TNT2 though.
An SBLive! shouldn't cost too much these days, about 500kr here in Norway (about 60$), I'm personally a fan of the MX300
Hansol's 710P is a great 17" monitor at a really good price, a friend of mine has one. 1600x1200 is actually usable on it unlike many lesser 17 inchers.
Get a decent keyboard and mouse too. After all, they're the most direct link between the user and the pc.
As cases go the Aopen HX45 is ok although it's not excactly exciting. Check out the HQ45 models too if you'd like a little color
A decent cdrom (ie. not the cheapest you can find) is a must-have, while the choice of a floppydrive is something you can do blind-folded.
I don't think I've forgotten anything now...hope this helps
Oh and...about the Compaq's. I hope your dad doesn't take offense of what I'm going to say but...crapcrapcrapcrapcrapcrap! There...I've said it.
I work part-time for a local electronics shop, in the service department. We get in a lot of Compaq's there, and boy am I tired of those machines...actually I think your dad would agree - all the people I work with hate Compaqs (The presario series mind, Compaq do make some decent servers).
We've just aquired a p2-450 wif 64mb and its like **** off a shovel...
and its the smallest quietest box i've used.
HAVE YOU HEARD OF THE NEW WILD FIRE SYSTEM FROM COMPAQ...
THEY WORK LIKE THIS...
EACH PROCESSOR 8 IN EACH BOX CAN ACCESS ANYTHING ON THE SYSTEM AT ANYTIME IT LIKES (850 MHZ A PIECE) REGARDLESS OF WHAT ANYTHINS DOING.
IT HAS ABOUT 4 GIG OF RAMBUS TO SUPPORT IT AND EACH PROCESSOR CAN RUN A DIFF OPERATING SYSTEM...
THERE MORE AL ASK ME DAD IF YA'S ARE INTERESTED
LET ME KNOW..
ooo god, no I can't.. well I supppose I could buy it..
If you get them a Compaq and it works fine then sure They're ok. But as soon as something goes wrong, and you have to come over to fix it...well lets just say that the next time you buy a pc the Compaq won't spring to mind quite so easily