Unlock All levels & items:
At the continue screen, enter D3BVG-M0D3.

Get to chest:
You dont have to use an anchor to get to the chest that says you need to collect the oven knobs. Get close to the still bubble platform right at the beginning of the goo and right when the edge is at the screen then let spongebob sink and he will be at the chest.

Here's what to use for the bosses in each level:
Giant Jellyfish
Item to use: Bubble Wand
What happens: It'll get trapped

Patty Bandit
What to use: Spatula
Happens: It'll get full of patties

Item: Wand
Effect: Unknown

Flying Dutchman
Item: Spatula
Effect: same as Patty Bandit

How to get the Power Ring:
Talk to Mermaid Man wearing a Hall Moniter badge. He'll think you're a TV repairman and give you the ring. While wearing it you'll be invinsible!