You have to use a socket in VB6 :
add the component Microsoft Winsock Control (Sp6) on your form
The link beteween PIC and PC can be done via ethernet trough a converter serial to Ethernet
like Lantronix Xport-03 or othe similar device.
With the socket you can catch the ascii flow and treat all items as individual datas.
You can add a protocol like modbus to encapsulate all the data if you want to be more secure !