You can install the beta  using VMWare or Sun VirtualBox virtualization.
Both of these support 64 bit Server OS environments. You can also install
the Beta directly on Windows 7 or Vista if you are running the 64 bit
version. You will need to follow some specific instructions to do it on the
64 bit desktop  OS's. You can find those instructions here:

http://msdn.microsoft.com/en-us/library/ee554869(office.14).aspx

Just install to a VM. That way you can control the OS, patch level etc. Do you
have a MSDN account? They have pre-configured VHD(s) you can download.

The downloadable SharePoint 2010 VHDs are built to work with Server 2008
Hyper-V. I have not had good luck getting them converted to work on Vmware.
So if you don't have Server 2008 with Hyper-V they may not work very well.

I downloaded the SP2010 beta  VM (was broken into about 14 parts plus a .exe file
to assemble them). I ran the .exe to build the VHD, then created the VM with the
existing VHD and got a Windows Boot Manager message and it wants me to insert
the installation  disc. This VHD came preloaded with Server 2008, so how do I fix
this?

I received a CRC check error after running the exe for part1. Don't know why
but another co-worker could create the VHDs successfully without requiring
anything else.

I can create the VHD no problem. It's when I attach it to a VM and try to start
it up that I have problems.

You are connecting it to a new VM in Hyper-V running on a 64 bit copy of Server
2008 or Server 2008 R2 right? It won't work on anything else.
You are connecting it to a new VM in Hyper-V running on a 64 bit copy of Server
2008 or Server 2008 R2 right? It won't work on anything else.

So the host machine must be running Server 2008?

Microsoft only supports 64bit VHDs in Hyper-V. Since SharePoint requires 64 bit
that means the downloaded VHD has to run in Hyper-V. Hyper-V is only available
in Windows Server 2008, or you can boot a VHD natively from Windows 7. But if
you boot it from the Windows 7 boot manager then you are running the VHDs
operating system natively and not really running as a virtual machine. I've
also had trouble trying to successfully convert Hyper-VHDs to VMWARE using the
VMWare converter.

So yes, the bottom line is that the Beta 2010 VHD needs to be run under Hyper-V
which requires Server 2008.

Can I install Server 2008 on a VM, then install Virtual Server on that, and
create a VM within a VM? I don't really want to upgrade to 2008 right now, as I
am using Server 2003 as my laptop OS and running VMs from it. It's got a bunch
of software on it and I would spend at least a week getting it back to where I
am now.

I don't think you can run Hyper-V inside a VM, so no you can't.

so I downloaded all that crap for nothing!

A few clarifications (I helped create this VM for Microsoft):

1) The package is a Hyper-V export created for Windows Server 2008 R2 “
if you are running that you can import it and all should be well. If you are
running anything else (Server 2008 Hyper-V, VMWare, etc) you will need to
convert and/or tweak the VM to work correctly. The most common fix is you will
need to make changes to the internal networking settings as the VM won't
retain the static IP addresses, etc unless the VM is imported. There are a few
brave folks out there that have successfully converted this VM to run under
VMWare and blogged about it.

2) CRC errors are generally a result of corruption during download “ if
you get those, grab a new copy of whatever file throws the error. This sort of
thing is fairly common unfortunately, and this is part of the reason it's
broken up into multiple chunks so that if you run into an issue you don't have
to download the whole thing again.

3) SharePoint 2010 is x64 only, and the OS inside the VM is Server 2008
x64. This means that only Hyper-V, VMWare, or Virtual Box can run it as Virtual
PC and Virtual Server don't support x64 guest OS's.

4) Hyper-V requires hardware virtualization support in the CPU “ this
means you cannot nest Hyper-V within any virtualization software (including
itself).

5) The OS inside the VM is Server 2008 “ this means you cannot use
Boot From VHD (a.k.a. the Windows 7 bootloader) to run directly from the
VHD as that requires Server 2008 R2. Boot from VHD also requires/highly
recommends that the VHDs you run from be sysprep'ed which isn't possible for
this VM as it's a Domain Controller.

So basically anyone that wants to run the SP2010 beta  must set up a Server 2008
machine first.

If you want to run it as distributed, you need Server 2008 *R2* (not just 2008)
with the Hyper-V role enabled, yes. There are workarounds that will allow you
to run under some other limited configs, but this is the intended way to use it.

I just wanted to play around with it a bit and check out the new features first
hand. The computer I intended to run it on has Server 2003.

Unless you want to jump through the extra hoops to get this working under VMWare
that's not going to work. Virtual Server/Virtual PC can't do x64 guests.

Windows Server 2008 (64 Bit) is required for Sharepoint. So, on 64-Bit
desktop sharepoint can be installed, i tried this and using it for testing.