I work with a lot of virtual machine images (my laptop is basically a host for Virtual PC 2004 SP1 and Outlook). I've been using the following steps to streamline my use of VPCs
Tired of having to remember different passwords for different VPCs? Set your Windows Server 2003 image to auto-logon
Sick of having to type in why you're shutting your image down? Get rid of the Shutdown Event Tracker
Do you boot multiple copies of the same image or share images with coworkers on the same network? Use SysPrep to prevent duplicate PC names when distributing images
Running out of hard drive space thanks to mega-sized VHD files? Create smaller virtual machines
Move your swapfile out to a different virtual disk. This frees up space on your main drive (for smaller .vhd files) and lets you use a single .vhd as the swap space for all your VPC images (caution, this limits you to one VPC running at a time with this config)
Build a library of VPC images by reusing base images as building blocks and adding changes to differencing disks.