Opinions please, on motherboards

Esteemed colleagues,

I am looking for opinions on a motherboard manufacturer, FIC (First
International Computer), and one of its MBs, a K8M-800M.

The K8M prefix sounds familiar to me when recalling AMD MBs, but FIC does
not.

Keeping the main focus on the MB question, the background info for the
curious:

I am considering the "purchase" of an eMachines T3104. I was not
particularly shopping for this model, but was offered to me as a substitute
for an eMachines T3882, which I purchased via rain-check for $99.99 (after
MIRs) at CompUSA. The store didn't have any in stock when they advertised
this and, under Michigan consumer law, they must offer a comparable
substitute at the same price point. The T3882 turned out to be a
discontinued model and no more of them were available. My brother had the
same deal and got a T4010 out of it. (I would have gotten the same deal,
except they ran out of those as well. It appears that CompUSA either can't
keep the eMachines on the shelves, or they are dropping eMachines
altogether.)

The T3882 & T4010 both came with an Intel Hazelton MB, which appears to be a
nice one, except that it has no AGP slot; that MB supports a high-end P4
CPU, even though the PCs ship with a Celeron D. I guess I have the image
that Intel has solid, well-designed, high quality MBs. The specs on the
K8M-800M seem to be impressive, with room for similar upgrade capability as
the Hazelton. But I have no feel for the manufacturer, which appears to have
a bunch of products geared to the gaming crowd, which *could* speak well for
the brand.

Our intended usage for this PC is basic home usage, internet surfing, NO
serious gaming (despite what my son pleads), moderate media work (create
DVDs from home video, burn MP3s). I might even try to fire up some WDSCi and
see if it can perform better than what I've experienced at work. I intend to
upgrade the memory (ships with 256MB) to 2GB when the right sale hits.

What somewhat surprises me about this substitution is that it comes with an
AMD Sempron 3100+ 64-bit processor and, apparently, the MB supports up to a
3600+ CPU.

As appropriate, RTFL (Links) references are appreciated:

Are there any issues with using 32-bit WinXP on a 64-bit processor?

Is there any way to know yet whether WinVista will run on this PC?

Anybody care to offer comparison opinions between the T3104 and the T3882?
And would this be considered a good substitution offer?

TIA,
Dan