Pictures are a tad out of focus for me to identify the coin, but my compadres should be along shortly to help you out. Welcome to the forum......
That's a £1 coin or one pound. Used here in the UK instead of a £1 notes. Worth about $1.60 unless there's something going on with it that I can't see.
Ya, pretty useless in the states for buying stuff. I just gave the exchange rate...it's normally around $1.60.