You can definitely add a phono pre-amp to adapt your TT to the Insignia.
You should be asking for recommendations for a high value phono pre-amp to go with your Insignia. Seems like somebody recommended one that was reasonably priced.
What speakers are you driving?
I'm not sure I would trust a $100 BestBuy stereo receiver to provide solid power. Do you know who makes them for BestBuy? That is a great price for a wireless networking receiver if the amp section is solid!
Also, looking at the photo of the back panel provided on BB's website, in the labeling on the right, it says "POWER CONSUMPTION ???A"! I assume this is from a pre-production sample! What does yours say?
I am also posting a picture of the remote in the hopes someone can ID the manufacturer: