The Microsoft Small Business Server should meet your requirements. If you want to read more about the software to see if it fits your needs, further information can be found on the Microsoft Small Business Center. No registration is required.
Go with HostGator. They give you unlimited space, unlimited domains, unlimited bandwidth and if you take the business plan, you can even get a toll free number. The business plan gives you free SSL and IP!
They have everything you need and they give you more than what you need.
http://www.hostgator.com/shared.shtml features are there.
Hosting plans vary from $4.95/Month to $12.95/Month (12.95 is the business plan).