"I am running Windows XP and it makes no difference which program i use, it is the same result."
"I should have previously mentioned that it only prints large from Groupwise and AutoCad. Works fin in Word..."
Your underlying printer services are okay then in XP. What you are describing is likely "font substitution", where the application is requesting font support and the font is not presented clearly by the application.
In AutoCad you need to ammend the standard printer definitions: "Test that your Windows system printer drivers work adequately for each of the devices that you want to plot to from AutoCAD. If not, use the Add-A-Plotter Wizard to install an HDI driver or create an AutoCAD-specific configuration for a Windows system printer driver. When upgrading from Release 14, use the Add-A-Plot Style Table Wizard to create a color-dependent plot style table (CTB file) for your office's standard color-to-lineweight mapping and make it the default plot style table (on the Plotting tab of the Options dialog box)."
You also need to ensure that the fonts you are using in your AutoCad (.HFX) and Groupwise application have been installed and enabled under XP. This would not be an automatic process for the XP upgrade procedure.
Your root problem is not XP per se, but integrating these older software and their fonts into current printer specifications.