This isn't hard. All you need to do is to complete all levels in Hustle Mode. This will take roughly 90 mins of gameplay. The hardest levels for me were the gravity levels. There are 33 total levels (don't know if that includes practice levels).

When you finish a level the extra time goes into your Time Pool and you need more than 500 seconds total over all the levels in Hustle Mode to get this. Play a level and if you think you can improve on your time, restart the level close to the end as you will already know the way.

This for me was harder than Hustle Mode. It takes roughly 20 mins, though, as there aren't very many levels to do.

This says "Find All" - which means all the locks in Stunt mode. It isn't hard, you should see them easily - they are green. The hardest one to find for me was on the second level, that one is behind the back wall as the 8ball tries to kill you. If you're having trouble finding the locks, check this thread:

http://www.ps3trophies.org/forum/hamster-ball/47456-rodent-king-stunt-lock-locations.html

Credit to Minarum for the lock locations.

See Vermin Champion

This is probably the hardest trophy in the game. Complete Stunt Mode to unlock Trial Mode levels, then get Watermelon times on all levels. What I did was play one level at a time until I got Watermelon. This may cause some frustration as some of these are pretty hard, but don't give up.

The Watermelon times are like a medal time to beat, except each tier is a different fruit. There are four of these, ranging from Peach (easiest) to Watermelon (hardest). It says what time it is at the top of your screen and also after you complete the level, it also shows your fastest and most recent times.

This is not to knock 6 opponennts out of the ring, but to beat 6 opponents in a game. First of all, make it an 8 player game and just 'camp' so you don't get knocked off and you'll get points. This does work in 2 player, thanks to footlesssushi for the tip.

This can be done on the Speedway II level (the icy one). Just before the spot where there are many mechanical arms trying to kill you, jump from the ramp and safely land (should be on the left road).

Do the same thing as the Flying Squirrel trophy, but use Speedy instead.

This could take a while, but the easiest way is to use Spiky all the time (once you unlock him) in Hustle Mode. If by the end of that mode you don't have the trophy, keep playing through levels. I found the level after Bounce I to be the easiest.

This isn't too hard, you should get it before you complete Hustle Mode. I did this on Gravity I.

Tips on maximizing your score:
1. Get more pigs
2. Finish levels quickly

What I did was first unlock Spiky. Then I went back to the Bounce I level and completed the game with Spiky. THIS DOES INCLUDE BONUS LEVELS WHICH ARE HARD TO NAVIGATE THE FIRST TIME.