Vista lets you share your Internet connection with other computers on your network.
Logically enough, the feature that lets you do this is called Internet Connection Sharing, which gets abbreviated to ICS.

ICS can be a great way of saving time and money: instead of needing a modem and a phone line (or a DSL or cable modem) for each computer that needs Internet connectivity, you can get by with one modem and one phone line (or the equivalent). ICS is particularly good if you have a fast Internet connection such as a DSL or a cable modem that provides enough bandwidth for several computers under normal circumstances.

Set Up the Computer That Will Share the Connection

Start with the computer that will share the Internet connection. First set up your Internet connection,and then use the Network Setup Wizard to configure the computer by taking the following steps. More »

The same way you take care of your car,with its oil changes,tweaks and tune up you should take care of your pc.Your computer (specially your Operating System) need alot of care,it is constantly working by modifying files,sometimes those modifications cause errors which then your pc logs and starts to slow down your computer, same has with the registry when it gets cluttered and alot of other sections.These are some good free utilities I have found, I think they do a pretty good job but to tell you the truth I dont use any, I always say you can find freeware thats equally good to paywares if not better,it doesnt look like the case with this.

If you have any extra cash,I really would suggest you buy TuneUp Utilities,I use it on a daily basis and might post a review on it soon.

This is our review for the top free system maintenance tools: More »