vSphere Hypervisro is a standalone product. It can be used to run multiple virtual machines on a single server hardware, but it cant be managed with the management utility vCenter server.
vCenter Server is required for the High availability features (VMotion, HA, FT etc) and resource management features (DRS, Storage DRS, etc) which VMware provides.
I've been looking into the advantages of virtualization, but I am still confused about the pricing. First off, I'm not looking to run a complex virtual mainframe or anything. I'm a one man show helping small business out, whether is watching or administering a sbs server or setting them up with cloud services. I'd like to virtualize their sbs servers for reduced downtime.
I'm confused about whether I can do this with the free version. I'm trying out ESXi (I think that's the one, I'm at home right now). To my understanding, when the trial is up I can continue using the hypervisor, but not vmsphere. If that's the case, how am I supposed to manage the server? Am I just supposed to log into the server and give up the ability to suspend vms?
Yes, you can create virtual machines for the enterprise servers and run on a Hypervisor server for better utilization of resources (CPU, memory, Storage etc).
We cant reduce the downtime much with a single vSphere Hypervisor without shared storage. Coz if the server goes down all the Virtual Machines(VM) will be unavailable until it comes back. Whereas two ESXi servers with shared storage can achieve maximum VM uptime with the vSphere features like vMotion, HA and FT.
Please refer the following Hypervisor FAQ for better understanding on vSphere Hypervisor.
http://www.vmware.com/products/vsphere-hypervisor/faq.html