Windows 2008 versus Windows 2000, network pauses

Hi,

We have two Windows 2000 SP4 servers and transfer a lot of data between the
two machines. These files are of varying size - 99.9% of the time they
transfer fine, but the other 0.1% of the time we see a pause on the sending
server which results in some applications 'locking up' for a period of time,
usually around 3 to 4 seconds.

The files are being transferred over a real-time mapped drive (e.g. file
copy to \\server\network_share\) on a gigabit LAN, both machines are
connected to the same GbE switch with no router between them.

I understand that the TCP/IP stack has been re-written in Server 2008. With
extended support for 2000 expiring in 2010, we're beginning the process of
thinking about the next logical migration - and wonder if the improvements
made to networking in 2008 offer the 'correct' upgrade path to 2000 (rather
than making the rather easier (from our current perspective) upgrade to
2003), and would be likely to eradicate the problems we currently see with
our network pauses. Alternatively, is there a simple configuration we've
missed in 2000 which would eradicate this problem?

Thanks in advance.