Also trying to determine what this is..or at least find out whether it's a weed! Thank you!

The little ones are Chenopodium album, Fat Hen or Lambs Quarters.

A "weed" is any plant you do not want growing where you do not want it growing. So if you decide you do not want them growing there they are "weeds", but if you want them then they are not "weeds".

Is there a woody stump at the base of the bigger one? If so, whatever was in there last year is growing new foliage.