I have a Dell 2400 running XP Home SP2.  I just wanted to give a plug for an XP PowerToy from Microsoft called Image Resizer.  It's only 521KB in size, and is very easy to use.  Once installed, you merely right-click on a photo you have saved on your computer, click Resize Pictures, and choose your options.  If you don't like the sizes listed, click the Advanced button, place a mark in the Custom field and you can type in your own size margins.  Previously I used IrfanView for this type of editing, but now prefer Image Resizer. 

 

http://www.microsoft.com/windowsxp/downloads/powertoys/xppowertoys.mspx