New PC fine tune

To tweak Windows, you want as little software as possible helping you reach that goal. The only option in this case is to disable anything you don't need in Widows. What version of Windows are you using? There are plenty of guides online that will show you how to tweak your OS for performance. But be sure you know what you're doing. Shutting off the wrong service or messing with the registry (especially the later) can really mess up your machine. The registry isn't something you want to mess with unless you REALLY know what you're doing, and chances are if you're asking these kinds of questions, you don't. No offense  

*IMPORTANT* Always perform a backup before changing anything. After installing Windows, updates, and the latest drivers, leave everything at default and back up the whole PC. If you know how to use Norton Ghost, this can really help you out. Create an image of your HDD using Ghost and if anything happens, just put that image back on your HDD and you're good to go. No lengthy installations or updates involved. This is best if you want to test out different settings or if you want to mess with the registry.

Hardware tweaking is whole other ball of yarn. If you plan on overclocking, you better make sure your hardware is up to the task by getting a good aftermarket cooler for your CPU, the case has enough airflow, do a really good job with cable-management to maximize airflow, etc.

Be prepared to spend a LOT of time doing this. I've been tweaking machines for performance for years and it still takes me at least a day to get mine from a clean wipe of the disks to totally optimized. Learning it all will obviously only make it take longer, so be patient, read carefully, but all of your hard work will definitely pay off!

Oh yea, and for my questions...

What OS?
Do you want to overclock your processor, video card, and RAM?
What parts are you using?

The first thing I do to Windows post install is:

1) disable System Restore
2) disable unused Windows Services (IE, telephony, Smart Card..., Windows Error Reporting, Web Client) Not sure what's safe to disable? Check http://www.blackviper.com/

3) If you're familiar with and comfortable editing the Windows registry you can do some cleanup there that WILL give you a performance boost, but be careful and KNOW your machine, know what your software needs to run at startup to behave properly and what it doesn't. THIS IS A WARNING. EDIT your Windows registry at your own risk. I recommend that you make a backup of the registry before editing.

With that said, after I've installed my apps I go to the Registry and do some cleanup to: Computer\HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
and
Computer\HKEY_CURRENT_User\Software\Microsoft\Windows\CurrentVersion\Run
and on 64bit Vista
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Run

and remove any unneeded startup entries (programs are notorious for throwing unneeded entries into these sections that bog your system down).

4) Check the Start Menu for unneeded startup items too. Start-->Programs (All Programs)-->Startup I like to keep very few items in there (ie, I don't need Adobe Acrobat to put a quick startup doohicky in there).

I think theses things will help tune your Windows install for snappier (do-it-yesterday) performance.

Okay, thanks for the info.
And to answer leo2kp's question, I have windows vista home premium. I don't think I will be over-clocking. I don't know what parts I will be using  . I am actually using a fairly old computer, but still in very good shape.

AMD Athlon64 2700+ (San Diego) 2.2 Ghz
eVGA GeForce 7800GT 256 MB
1 GB DDR RAM
ASUS A8N-SLI Premium Motherboard
250GB HDD

The system was built in Dec 2005. I put Windows Vista Home Premium on it about 1 year ago.