First, you don't need to update first in order to connect to PC.  You need to use the mini usb port that is on side of the unit under a cover.  If you use the one on the top, it will not connect because that is for connecting to the VCI or Programmer.  As for wireless connection, you can try a open public wifi connection. I don't know were you are but you can look arounf in your area.  Usually public library's have open free wifi connections where you can get the updates.  I would strongly suggest that you connect it to the PC first and create a backup of your existing software before you update it.

If you are connecting to the VCI with the cable, that means you are on the wrong port.  The port you are looking for is on the left side where your hand is.  It is under a cover that you need to open with your finger nail.  Under the cover is a small USB port and a slot for a memory card.  That is the port for the PC connection.

 Attached are two pictures of the port you should be connecting from the tablet to the PC.

I have always updated my tools via wifi and its so easy that it takes seconds in some
cases.

Did you try a different computer and a different cable.  The tablet needs to be on and ready to be used when you plug in the cable to PC. Then the screen changes and then has a button to turn on PC access, did you get this screen?