leaky injector pump and vag com confused?

Ok I have an injector pump that is leaking on the lower have and I have seen the youtube video on how to replace the gaskets (very very good) The last part of the video show the mechanic running vag com some sort of measurement (couldn't hear what he said)

My question:

I have a 2001 beetle tdi. What vag com software and cable do I need. I want the usb version of the cable.

Since I'm not a full time mechanic can I use the Ross Tech VCDS Lite version?

I really don't want to spend $300 of this.

Here:
http://www.ross-tech.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=VCKII&Category_Code=VAGCOM

A registered version of VCDS-Lite will also work. However, Ross-Tech does not supply hardware (an interface) for VCDS-Lite, so you must source this yourself, and getting it working with the free shareware version prior to registering it entirely up to you and your hardware vendor, whereas the system that jetta ,97 recommended above is a complete hardware/software package which is guaranteed to work and fully supported.

-Uwe-