How to speed up My Computer?

Making your system perform well in relation to surfing and using the internet is a task that can seem daunting at first.  However, even if you think you have the best system in the world and the fastest internet connection available, spend the time analyzing and tuning your system's performance. It is well worth it, if only to understand your computer and connection so that when it does slow down you have a good idea why and where to look.
It's beyond the scope of this web site to go into any detail on computers - the focus is the internet. You can find many other sites and references which will help you if you are concerned about performance.

Hardware

A good place to start is to look over your hardware. Some questions you should answer are:

• How big are your disk drives? 
• How much RAM is installed on your system? Given adequate processor speed and disk performance, this is probably the most important question. 
• What is your processor speed?

A good rule of thumb, especially if you are buying a new system, is to get as much disk and RAM as you can afford. Processor speed will be good for things such as running Java, animated GIFs and VRML.
It's a good idea to get more than one disk if you can. This allows you to spread your files over the disks and thus improve performance. It's even better to install more than one disk controller, as this spreads out the I/O even more.
If you only want to upgrade one thing, then a general rule to follow is to add memory.

Operating System

Which operating system are you using? If you are purchasing a new system, get one that will run Windows NT as well as Windows 98 and check out the differences between the two systems.  You can create a dual-boot partition and boot up to each one as needed. I like Windows NT because it's an extremely stable operating system and very well supported by vendors and in the marketplace.
That is assuming you are purchasing a personal system for your own use.  If you are purchasing a server system which will host a web site, you have many more options, including Linux and straight Unix.  Each choice has advantages and disadvantages, just be sure to get a good match between operating system, hardware and your own experience.

Things to do in software

The operating systems that I am most familiar with are Windows NT, 95 and 98.  In those operating systems, check your page file parameters. I've found that having a small page file can deteriorate performance very quickly. In addition, consider creating a page file on a second disk (and on a second disk controller if you can).
Take advantage of your browser cache. Make it large and, if possible, put it on another disk drive. This does introduce the annoyance of possibly looking at old pages (a refresh will cure that), but it will make your surfing faster.
One product that I use which is pretty cool is TweakDUN. This allows you to optimize your registry settings (especially the RWIN parameter for faster internet connections). I used it and improved my performance considerably.