WINDOWS 
First thing to do is set your system to “Network Server” if you have 64mb of ram or more (if you have less than 64mb ram leave it set to desktop system).  You do this by right-clicking on MY COMPUTER...go to properties...performance...then File System.  Just select Network server from the list and re-boot. 

After you do that, optimize your swapfile.  Follow the same procedure as above, but select Virtual Memory instead of File System. Click “Disable Virtual Memory” and re-boot.  After your system re-boots, defrag your hard drive.  Once the defrag finishes, go back to the virtual memory page and enable virtual memory again. Then select “let me specify my own virtual memory setting”. 
Set your swapfile to 2.5X your system ram.  (Ex. if you have 64mb ram set it to 160....128mb ram set it to 320.)  To set it manually, set the Minimum and Maximum values to the same number.  Click OK and re-boot. If you have more than 128mb of ram, set your swapfile to 2X your system ram, there’s no reason to use up that much hard drive space.  The more physical ram you have, the less windows will use the swapfile.  Some people with 256mb ram or more even recommend disabling Virtual Memory altogether, but I disagree with that.  No matter how much ram you have, some applications will still use virtual memory. 
 

CACHE SETTINGS
Click on start...then run...and at the command line type SYSEDIT.  When all the windows open up, click on your system.ini file.  Scroll about ½ way down, and you’ll see a line that says [vcache]. 
Just under it, add the lines: 
MinFileCache=1024 
MaxFileCache= ½ of system ram 
If you have 64mb ram, it should look like this: 
[vcache] 
MinFileCache=1024 
MaxFileCache=32768 

Close sysedit, save the changes and re-boot.  Some people have told me that ½ system ram is too high, but without any tweaks, windows by default will use as much memory as possible for cache. 
Limiting it to half, still give’s windows a nice big cache, and at the same time leaves much more available to your applications.  You can fiddle with the max setting, different systems might yield 
different performance.  If you have a lot of ram (128mb +) you might even want to set the minimum to a higher number.  When calculating the min and max numbers, just multiply how many megabytes you want to use by 1024.  For example 32 X 1024 = 32768.  Another often overlooked tweak that enhances performance dramatically is enabling DMA on your hard drives and EIDE Cd-Rom drives.  Enabling DMA not only will increase data transfer, but drops CPU usage.  Just about every hard drive in the past 2 years and most Cd-Rom drives made in the past year will work fine with DMA enabled, if you’re one of the unlucky ones…sorry. 
Once that’s done, you should notice a difference in overall performance, both while gaming and during regular usage. It’s always good to specify settings on your own, rather than letting windows adjust them on the fly.  Another good thing to do is delete any items from your startup folder.  Most of the items that load in there are not absolutely necessary, and will just hog memory and resources.  My startup folder is completely empty. 

MODEM
To help out with on-line games if you use a modem, there are a couple more things you can do. (This is only for analog modem users...some of us haven’t been blessed with the fat pipe yet)  First download a utility called MTUSpeed Pro.  Install this program, run it and click on the “Optimum Settings” button.  Then Click on the “Update Registry” button and reboot.  Windows by default isn’t optimized for modems...this changes that.  For most people the MTUSpeed’s default optimum settings are the correct ones. 

PORTS
My modem is on COM2 and uses IRQ3.  If yours is different, substitute where necessary. (You can find out what your modem is .using my right-clicking on My Computer...go to properties...device manager… modems...open the directory, select your modem and click properties.  Under modem it will tell you the Com port, under resources it will tell you the Irq) Go back into device manager, scroll down to modem...select your modem and click properties.  Select Modem, and under maximum speed set it to 115200. Then go to connections...click on port settings...and put both sliders all the way to the right.  Close your modem properties. Now while still in device manager, scroll down to “Ports Com&Lpt”.  Open the directory, select the port that your modem is using and click properties.  Go to Port settings, and under “bits per second” set it to 115200. 

If the port for your modem isn’t there...you can do it manually.  Run sysedit, and scroll down about half way in your win.ini file. You’ll see a few lines that look like this: 
[Ports] 
LPT1:= 
LPT2:= 
LPT3:= 
COM2:=9600,n,8,1,x 
COM3:=9600,n,8,1,x 
COM4:=9600,n,8,1,x 
COM1:=9600,n,8,1,x 

Change the “9600”’s to 115200.  It’ll look like this: 
[Ports] 
LPT1:= 
LPT2:= 
LPT3:= 
COM2:=115200,n,8,1,x 
COM3:=115200,n,8,1,x 
COM4:=115200,n,8,1,x 
COM1:=115200,n,8,1,x 

Close Win.Ini and save the changes. 
While you’re in sysedit, there is one more thing you can do, it’s experimental and may not work for everyone. 
Go to your system.ini file, scroll down to the [386Enh] line.  Directly below it add the line: 

Com2Irq3Buffer=2048 
(Substitute your settings if different) 

Close sysedit, save the changes and re-boot.  All the lines that were added to .ini files have to be typed EXACTLY as you see them. They are case sensitive.  The modem tweaks will help with browsing and just about everything modem related. 

Always install the newest drivers, patches, BIOS and firmware and tweak your windows settings.  If you follow this guide, just about every aspect of your system’s performance will increase and at the same time, you will increase it’s reliability and compatibility. .