You can install two or more versions of Office onto the same computer, so since you already have Office 2000, you could install Office 2003 in addition.
During the install of Office 2003 keep an eye on the options, and change the default location of where Office 2003 expects to install itself to some other location of your choice. If there is an option to 'remove' previous versions, de-select that option.
There's more detailed information and guidance here;
http://pubs.logicalexpressions.com/pub0009/LPMArticle.asp?ID=762
That should explain the procedure and possible pitfalls much better than I can, in particular licensing issues.
One thing I note from elsewhere, ( http://support.microsoft.com/kb/218861 ). You cannot have more than one version of Outlook installed. If you use Outlook, then you should be aware of this.
Read those carefully and see if they help.
Good luck.
Mark
I am upgrading from Office 2000 to Office 2003 on my Windows XP system. During the install it will delete my Office 2000 version. Does it verify the Office 2003 product key before or after it has deleted my Office 2000? If it doesn't validate then I don't want my Office 2000 deleted.
I ask this because I have purchased this Office 2003 used from someone whose computer completely crashed and was scrapped. I suspect that Microsoft thinks that this would be a second use of the same product key and fail to validate. Is that so?

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