Some software files have file version information only, and some have that and product information. WinZip usually has both, so you can use the SoftwareProduct table to match WinZip to a product name. You need to link at least SoftwareProduct to SoftwareFile and R_System.
Try pasting this as your query statement (edit query statement > show query language):
select distinct SMS_R_System.Name, SMS_G_System_SoftwareProduct.ProductName, SMS_G_System_SoftwareProduct.ProductVersion, SMS_G_System_SoftwareFile.FileName, SMS_R_System.SMSAssignedSites, SMS_R_System.LastLogonUserName
from SMS_R_System inner join SMS_G_System_SoftwareProduct on SMS_G_System_SoftwareProduct.ResourceID = SMS_R_System.ResourceId inner join SMS_G_System_SoftwareFile on SMS_G_System_SoftwareFile.ResourceID = SMS_R_System.ResourceId
where SMS_G_System_SoftwareProduct.ProductName = "WinZip" and SMS_G_System_SoftwareProduct.ProductId = SMS_G_System_SoftwareFile.ProductId
In addition, on the General tab of the query properties you can set Limit to Collection to your W2K collection.
You can go back into Show Query Design and edit it as needed.