Quick overview:
If you have often had unexplained crashes with Explorer or many programs and windows open at the same time, this may be due to the memory management behavior of Windows, as it is designed to write as much information as possible in a block of working memory. As this causes fragmentation of this memory and therefore instability, you should run each window and each program in its own memory area.
Windows XP - Stabilize and optimize Explorer
However, on computers below the magic 256MB limit, this will reduce the speed of the computing power. And this is how you proceed:
1. Make sure that under Start > Control Panel > System > Advanced > Settings > Advanced the option Processor scheduling is set to Programs as shown in the picture.
2. Now open any Explorer window, such as My Computer, after you have confirmed any pending changes with OK.
3. Now click on Extras > Folder options at the top of the bar and switch to the View tab.
4. Use the scroll bar to move down until the entry Start folder window in a separate process becomes visible.
5. Click on the small box to tick it. A final confirmation with the OK button confirms the changes.
Important note: If you have run the tip together with Memory optimization for Windows XP and encounter problems, you will be helped here: Problems with Windows Tweaks Performance Focusing Tip! ATI Radeon owners are affected here. We are giving you this notice because some (but very few) users have experienced login difficulties.

On Windows Tweaks you will find time-saving tech guides for PC, software & Microsoft. For a stress-free digital everyday life. Already we have been "tweaking" Windows since 1998 and just won't stop!