There are managed servers, managed servers, reseller servers, co-location servers, and shared servers.
Managed Servers:
This just means that you'll tell a tech support guy what to do and he'll do it for you.
Unmanaged Servers:
Here's your IP, good luck configuring the server. No tech support given. Usually setup with webmin.
Reseller:
Someone gets a server and resells webspace on it. The hosting company usually gives commission to individuals running reseller plans.
Co-Location:
Your given a location and sometimes bandwidth to plugin your own server or rent one of theirs. The installation, hardware, and configuration is your duty to make.
Shared Server:
One computer but with several users uploading and running their site off of it.
Dedicated Server:
You get your own computer to run your site. You can either choose managed or unmanaged.
If one user uses all the processing speed and slows down their site the other users are effected too with a shared server. Usually shared servers give an average of 40 Gigs bandwidth at $7 a month while dedicated servers can give up to 2000 gigs bandwidth but also cost $100 a month. If your site users a lot of bandwidth or processor intensive resources like MySQL, you're likely better with a dedicated server. Otherwise, you should save money with the shared servers.
Windows is more processor intensive, so it's almost always better to go with Linux. PHP is an excellent replacement for ASP, and you can easily install it at your home windows computer. See the getting started with php and mysql article).
It's not recommended you get your domain name from the promotional offers of hosts. Register it yourself with a domain name registrar you can trust. See our Choosing A Domain Name Article.
This site is hosted by Server Beach. They have even $100 plans with 2000 bandwidth. Personally I can recommend DreamHosts, or Lunar Pages as a shared server. Really it's best to see many hosting companies before selecting. We've compiled a list that may be useful. Rackspace.com has wonderful managed services, meaning you can call them anytime 24/7 and get support, but they're a little more expensive. Hostonce.com is the worst host ever, stay away from them.