I have this problem.
My motherboard is an ASUS A7M266VM. It has two USB sockets on the back. It has 4 more USB headers on the mobo. It came with a board to use two more on the back. And the case I have allows for two mounted on the front.
I have found that if I have anything plugged into a certain three of these, the system hangs. I can only use the 2 addon USB ports at the rear, or the lower of the two sockets on the front of the case. Otherwise the system hangs when Checking Module Dependencies, or as soon as I plug something in.
My solution has been simply not to use the offending sockets!
The mobo has an nVidia nForce 220D chipset. I've tried adding "noapic pci=bios" to the LILO append= line, to no avail.
Actually I have had enough of this mobo (I have a raft of issues with it) and I hope at the weekend to put my old PC Chips 810LMR back in. Okay it's not as flash as an ASUS but at least it runs Linux straight out of the box!