Some of those issues are very familiar, I had trouble with my wireless network and even more when I installed Internet connections.
First thing: DON'T PANIC, there is no technical problem that cannot be solved.
Couple of things you should know:
If you want to connect to the internet using your wireless, you obviously need to have a home internet connection and a modem-router that supports wireless connection. Stealing other people's internet is an offense. Keep that in mind. Now your router/modem (or both in one device) is the very device that allows you to connect to the
internet, the wireless adapter is a tool that lets you establish a link between your PC and your router/modem, so you don't have to connect them with a cable. A DHCP is a service that leases an I.P. address for each connected device.
esprit if you want to connect to the web, you'll need to buy a router, some internet providers give it for free when you buy a connection from them. Supposing you did that, you scan for networks with your wireless adapter, when you find your router you link to it. Then you will have to type the routers I.P. in your browsers address bar, thats how you get to it's interface. In the interface you'll have to enter user name and password to acess the router as a measure of security (otherwise every punk with a wireless adapter can enter and change your router's properties). Then enter your broadband nickname and password (given to you by your internet provider) and there you go, you can access the web.
Its important to set up an encryption (same key on router and PC) so only your adapter can access the network and also to change your router's administrator name and password. If you forget it or something goes wrong with the connection you can always reset the router (just back-up router settings on your PC so you wont have to reconfigure it).
TPS what do you mean it stoped working? You cant get to the web or the PC problem you mentioned? for the PC I would first check what happens when you unplug it from the router and cancel the connection.
Hope i was helpful
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