Re: Tire wobbly
The reason those tires are folded in a box is because they have a Kevlar bead and are foldable. Cheap tires have a metal wire bead and can't be folded. The better tire is the Kevlar beaded one. I once spent over 100 dollars on a set of Kevlar tires for my road bike and they came in a package folded too.
Even though those tires at Walmart are Kevlar I don't know if they are any good or are "lumpy". I don't remember how much they cost buy I think less than $10? Anyways seem way too cheap to be much better than the stock tires.
Hopefully you already fixed your problem but if not I would recommend getting a descent tire at a bike shop since you have a nicer wheel now. Tires make a huge difference on the feel of your ride for sure!