You haven't given up yet, haven't you?
Try not to spend too much on the whole system.
Asus and
Abit i875P-based mainboards are both excellent. There are competitive chipsets from both SiS (655TX) and VIA (PT880) for the price, but in term of absolute quality, I don't think any of the alternatives match Intel's chipsets yet.
Don't touch the Presscott processor unless you are willing to risk yourself with the promising new IGP 9100 Pro chipset from ATI (still no tangible mainboard based on it tough).
I don't think you'll need many additional functionalities like more than 4 USB ports and IEEE 1394 ports. Ditto for gagabit Ethernet and RAID (any). Keep it simple. IMO, an
Abit IC7 would be just fine. Even the
IS7-E2 (based on the i865PE chipset) would be since Abit has a BIOS that enables a PAT-like feature on their i865PE boards.
Asus' i865PE boards do that too BTW, but they cost more for no other apparent reason than brand name.
If you've completly lost your mind, there's always the
DFI LANParty PRO875B, but only if...
Oh and a Hitachi 400GB SATA drive, a 74GB Raptor and a Radeon 9800XT graphic card are, needless to say, over the top for her box ;-)