Hi there and welcome
The easiest way to do this is via Dropbox.
The reason is then its all wireless, you have a online backup, and you can also transfer the other way (wirelessly).
On your computer, go to www.dropbox.com and click on download in the top right.
Download and install it creating a free account.
Once installed, you see a dropbox folder. Copy your photos to it like you would copy any files.
Once done, on the ZenPad, go to the Play Store and download the app Dropbox
Open it, sign in with the same account and you will then see the photos that you can save to the Zenpad or just view online.
I can also do these steps for you, and have made a request via Additional Services. This is optional, and if you choose to do this, I can, with your permission, remote into your computer while you watch and do all these steps (and deal with any problems that arise during them) for you. Or if you do not choose to take this service, we can continue here. This is no problem at all. Just let me know please.
Let me know the results please