Not really knowing what server you are actually looking at we can only guess.
Adding to what GregL and Jim B said.
My guess is you're migrating from Server 2003 Standard, IIS 6.5, Access 2007 using ASP classic code pages connecting via OLEDB static. You might be planning on importing your Access using Upsizing Wizard (which kind of works most of the time) or you might try the 32bit app Import/Export.
For your new setup I'm thinking, MS Server 2012 Standard that is licensed for 1 physical and 2 virtual installs. That would offer you the option of running SQL and IIS independently in different VM's. But, that might not be the best approach in your case.
DO NOT: run public applications from a hyper-V HOST OS. I would also suggest not to enable RDP on the HOST. Think of the host as the power cord to your server. If it breaks, you'll need to be onsite to fix it.
YOU CAN: install IIS in a Virtual Machine > Memory depends your code code, if you run ASP classic or .Net
YOU CAN: install MS SQL in a Virtual Machine > Size of your VM depends on your Edition of MS SQL. Express versions offer up to 10GB of total overhead with data (Compare Editions).
Plan your server as you see it 7 years from now. Example: Virtual Server Drive Size day one, 128Gb, year 5 1.5TB, planned 3TB.
IIS 7.5 and above does work very well in a Virtual Environment. Running MS SQL Express designed for your OS in your virtual environment is also good. The idea behind it all is to be able to run more from a single physical server than before. If it runs in a stand alone install it should be just find in a virtual install. Excluding Datacenter versions that profit from using all physically attached devices and memory. Having both IIS and SQL Express on the same VM reduces my admin time by not having to watch a second server. Unless you're planning on running a Datacenter version, then you want it on it's own physical machine.
Here are some numbers off of my Server 2008 R2 Standard. CPU 3.3Ghz, 8 core, 1 Physical 1 Virtual Windows servers, 2 Virtual Ubuntu Servers, 2 Win8 Virtual Desktops, 2 Win7 Virtual Desktops.
IIS = 3.4Gb (27 IIS www sites, 3 ASP Classic 24 .Net)
2008 SQL Express = 1.14Gb (28 dbs active)
OS 2008 R2 VM = < 2Gb
Total Memory 10Gb never has used it all.
Your 64Gb memory machine will be nice but take your real numbers and tune your system to match plus 20% or what the OS recommends.
Regarding the hackers, they do exist, but so do scripts. Plan your system recovery as if you're planning on being hacked every night. And practice your recovery process until it's perfect then when it's needed it will actually work.