How to Fix Windows Xp Slow Startup?

[Edited to improve clarity]
Try downloading two of Microsoft's Sysinternals utilities, Autoruns and Process Explorer. They are the first two listed under "Top Ten Downloads."
http://technet.microsoft.com/en-us/sysinternals/bb842062.aspx

Autoruns shows you everything that starts when you start your computer. If you see something that shouldn't be there you can uncheck the box to prevent it from starting when you boot. After disabling an item and rebooting, make sure you can still run all your applications normally. If so, then wait a week or two and then you can delete the unwanted startup. Be very careful what you disable or delete! If your PC doesn't start up normally, start in Safe Mode and re-enable the item(s) you disabled.

Under Options, check "Hide Microsoft and Windows Entries." That will remove clutter and prevent you from disabling the important stuff.

Process Explorer shows you everything (all the processes) that are running at the moment. Set it to replace Windows Task Manager. Process Explorer is benign; it doesn't delete anything. It does let you stop any process, such as a frozen application. Also, when nothing else works, ProcExp has a "Shutdown" option in the File menu.

When you hit CTRL+ALT+DEL, Process Explorer will pop up instead of the old Task Manager. I like to click on the "CPU" column to see which processes are using most of my CPU's time (expressed in percentages). If your computer is not overloaded, the first item shown will be "System Idle Process." This indicates that your CPU is loafing (with the current combination of processes).

Under "View" you can set the Update Speed to 5 seconds to keep the display stable long enough to study it.

 

Show the pc a picture of a mac!!

Upgrade to vista it's much more stable even though it takes up more room :)