Standard cards are entry level. they will not work for HD video capture. low cost cards.
Ultra II, now re-maned Ultra, are your mid grade cards. these cards are generally class 4 but there are some class 2 from early productions so be careful. Class 4 is supported by most HD capable cameras but some require class 6.
Extreme III, and Extreme HD video are the same for the most part. Extreme HD video replaced Extreme 3 and has been speed bumped from 20 to 30MB/s. Both are capable of HD video. Extreme III is class 6 where as Extreme HD video will be class 6 for older production class 10 for the newer production. to make it more confusing starting very soon they will be changed to UHS-1 a new SD specifaction.
Extreme cards will be class 10 30MB/s cards
And A new Extreme Pro 45MB/s card was just announced which is rated as UHS-1
If I were you I would go with Extreme HD video or Extreme 30MB/s. These cards will work for anything you want to do and give you the best performance. Not only that but they have a life time warranty as well. I know it is confusing but I hope it helps.