Here is the full list of all 38 Toki Tori achievements. It takes around 10-12 hours to unlock all of the achievements on Windows.
Collect all ten snowflakes that appear in December before they melt
Stand in all sun beams
Find her.
Stand in the beam in Test Lab bonus level 6
Collect 1000 eggs
Suck up 30 slugs
Finish all hard levels
Complete all Bubble Barrage hard levels
Complete all Slimy Sewer hard levels
Freeze 50 monsters
Press "Try Again" 10 times on one level
Make Toki Tori dizzy
Stand in the beam in Test Lab bonus level 2
Trap 30 ghosts
Complete all Creepy Castle hard levels
Trap Toki Tori between two Switchbricks
Collect 500 eggs
Complete all Test Lab normal levels
Complete all normal levels without using the Wildcard
Watch the ending
Complete all Bubble Barrage normal levels
Complete all Forest Falls hard levels
Finish Forest Falls, Bonus 3
Stand on an ice block for 12 seconds
Use 32 bridges to finish a level
Use 42 InstantRocks™ to finish a level
Complete all Slimy Sewer normal levels
Finish a level without using all items
Collect 200 eggs
Get really close to a monster
Find the Tunnel of Love
Complete all Creepy Castle normal levels
Play Toki Tori for 60 minutes without being idle for more than 2 minutes
Telewarp directly into lava
Collect 100 eggs
Fall into the lava
Complete all Forest Falls normal levels
Make Toki Tori look sad