Hey Texan203...welcome to the OB!
As for cutting back an old spike on a phalaenopsis, there are a couple rules that folks go by.
If it has turned brown and dried up, cut it off at the base of the plant with a clean cutting tool. This spike is spent and will not produce additional flowers or a keiki (baby plant).
If the spike is still green, you can do one of two things. The first is to just cut it off at the base of the plant with a clean cutting tool. This way the plant can conserve its energy stores for its next spike (this is my personal preference). Alternatively, you can leave it on in the hopes that it will produce a keiki or additional blooms, either at the spike end or on lateral branches. Not all green spikes do this, but some do, which is why some folks leave them on the plant.
I hope this helps.