I read an article about thread and needle size and she ( don't remember who now) said she li!as to use a "quilting" needle, instead of a sharp, which I guess a lot of people use.
You need to match you thread to your needle. If the eye is tiny don't use a thicker thread.
As for what kind of thread, I have read here on the board many different opinions. Glide has good ratings, and I plan to try it myself someday. Lots of ravings about Aurafil. I personally have used gutermann with good results. Right now Im using Connecting Threads brand, which is working fine in my Janome.
To answer your question about top and bobbin, no not necessarily, but as a beginner, I would, and do, keep them the same type, weight.
I hope this helps. Many blessings on the wedding. We need pictures when the day comes! Gina