Hi patrickjw
It should be fairly straightforward to move your Outlook data to a new system. I'm assuming that this is a standalone PC, not connected to a fileserver?
Outlook stores it's data in a file with a .pst extension. On my PC (Windows XP and Office XP) it is called Personal Folders.pst and is found in the C:\Documents and Settings\Sean\Local Settings\Application Data\Microsoft\ folder. All you need to do is find your PC's equivalent of this file (use search on the start menu) and copy the file to a folder on your new PC.
The file must then be imported into your new Outlook. Start Outlook and choose file | Import and Export. Choose Import from another program of file and press next. Choose Personal Folder File (.pst) from the list and press next. Click Browse and navigate to the .pst file you just copied and click next. Make sure Include subfolders is ticked and select Import Items into the same folder is selected and Personal Folders is showing below that. Click Finish.
Your data should then be imported into Outlook, folders intact!