[CentOS] Laptop for CentOS-5

I have a defective HP-Compaq nx9420 and so I am looking to replace
it.  I have pretty much decided to buy no further MicroSoft based
products and would very much like to hear recommendations for a
suitable notebook host to provide me with Linux based alternative.

Given that all the basic functionality required is provided, the
main thing that I am looking for is reliability of the host itself. 
I do a deal of traveling so physical robustness is an issue.  But I
also use my notebook for hours at a time, generally every day. This
means that I am typically on a/c current rather than batteries and
that power regulation and heat dissipation are also concerns.  The
power regulator circuit is in fact what I believe has failed on the
nx9420.

Not infrequently I have the notebook on my chest or lap while
working at home.  So the ventilation clearances provided by a flat
desk support are frequently absent and the notebook design must
accommodate this.

I would like to use CentOs as this is what I am most familiar with. 
But, I am open to CentOS alternatives like Ubuntu or even a
non-Linux alternative like a PowerMac with OS-X.

I have already looked at the Dell site on the basis of a friends
recommendation. While Dell mentions Ubuntu is available for some of
their notebook computers they do not seem to provide any way to
actually configure a system with it.

So, my desires are:

WANT:

Robust construction
Reliable quality
Reasonable weight (< 2.5 kg all in)
Supported sound and video reproduction of reasonable quality
15-17" lcd screen
Out-of-the-box support for wireless networking
Battery life > 2.0 hrs.
Not MS-Windows

PREFER:

64 bit
core duo 2
2-4+ Gb RAM
120+ Gb HDD
writable multi-mode DVD/CD drive
CentOS-5+

Your system suggestions, both for hardware and OS, are most welcome.

-- 
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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
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