Same Sheet.
Yes, Defined tables.
Two separate tables: here's my reasoning - Table1 is for a barcode scanner data entry...using a defined table is nice because when you scan the data into column A and then into B, it goes to the next row-column A automatically without keyboard input. I can focus on scanning with an occasional glimpse back at the laptop to make sure nothing was missed.

I used to do this all with one table, as you suggested, by unlocking columns AB then protecting the sheet and unchecking Select Locked Cells to make data entry easier. This worked great for me but I want to share this template with my team.

In the end what I'd like is a way to scan data into the two columns without keyboard input, and be able to copy the massaged data into our database tool. I thought if I could set it up with two Tables I could avoid the need to protect and unprotect the sheet for the most user-friendliness.