Are you planning to keep the system running 24/7? I suggest for this purpose it's better to either run just Ubuntu without the hassle of configuring system on vmware for printer sharing or share printers though your XP system.
What kind of printers (network, usb, scsi...) are you using and for what other tasks are you intending to use your Ubuntu installed on vmware?
And what users will be suing them? Local users using just that machine or network users? Please give more info is it's possible.
It's simply too complicated to be using a system installed on vmware just for printer sharing. Also, there are some minor problems with usb support in vmware and printer support in Ubuntu. Using cups printing system generally does the job but not in all cases.