first and foremost, you need to make sure your ISP has ports open for you to host. port 80 is what webservers operate on, however you can reconfigure them if your port 80 is blocked or closed.
to find out if your ports are open, go to http://www.grc.com/x/ne.dll?rh1dkyd2
test your ports by clicking "all service ports" most internet providers leave ports open these days. comcast in my area does, as does ATT DSL.
if your ports are open and not stealth or closed, you are good to continue.
windows actually has support for hosting ASP/HTML built in.
i run apache web server (php/html) on a windows XP machine. next however i am setting up my old junkjer computer and installing a freebsd server or linux server with no GUI (no windows, just a dos like mode) this will reserve more ram and cpu usage for hosting the website making it more responsive when i get intomore advanced drupal sites and stuff agian.
websites are hosted via software components called servers. you can download all in one apache server installer packs. look for things called XAMMP or LAMMP on google.
setup your server software. you may have to look through youtube tutorials or google forum tutorials for help getting it up and going. be prepared, it culd take a day or so if you are not technically inclined. it is possible though, i taught myself everything i know, years ago. just stick with it if you decide to get into it.
once you have your server setup, you will have to install your website script or start writing html by hand or using dreamweaver or another web site builder.
once you have a site setup, you need to start getting your server "live" on the internet. this isnb't too hard, and there are plenty of youtube tutorials about it, i can also help when you get that far down the road.
you can setup a free domain name at dot tk (.tk) like i use until you decide you are stable enough to go with a dot com, net, ws, etc.
get started and when you need some help i can offer assistance.