Poker Hand Rankings
Poker Suit Rankings
In poker, suits are not officially ranked.
For friendly games you could set your House rules to rank by suits. It depends on whether you will allow suits to matter or not. You would decide if you allow ties or use the suits (or some other method) as tie-breakers.
If you need a guide, in Bridge where suits are ranked, highest to lowest is in reverse alphabetical order; Spades, Hearts, Diamonds and Clubs.
Poker Hand Rankings
References
Hoyle's Rules of Poker and Ranks of Poker Hands: http://www.hoylegaming.com/c-16-rules.aspx#poker