broadcasting dhcp for ip adress failure on boot

my situation is as follows:

got a compaq laptop nx9020 and knoppix 3.7. this is a realtek 8139/i810 nic, pretty common.

with normal boot, it hangs on "broadcasting dhcp for ip adress". must turn off the computer

if i boot with "knoppix nodhcp" i get to boot into the desktop, but any further attempts to gain dhcp or configure the NIC fails. (ifconfig eth0 hangs, netcardconfig fails). shutting down linux results in hanging on "Shutting down eth0:". must turn off computer.

if i boot with "failsafe" i can configure dhcp to work from within knoppix, but then, not much else works.

if i boot with kernel 2.6 "boot knoppix26", the NIC works, but then my USB drive doesn't work properly (i can browse it, but can not create a persistent /home directory there. this works fine in 2.4).

could anyone take the patience to help me a little? i am pretty new to linux :)