Higher Jump

Level 1: Helps quite a bit, especially in the later levels! 8/10

Level 2: Perfect, you can just skip a lot of platforms. 8/10

Level 3: A little too much of a good thing, this will cause you to overjump and miss. 5/10

Extra Life

Level 1: Extremely useful! 10/10

Level 2: Very useful! 8/10

Level 3: It's still useful. 7/10

Rope

Level 1: Lame. 3/10

Level 2: Gets in your way more than it helps. 3/10

Level 3: It's still lame. 3/10

Scarecrow

Level 1: Excellent!  That takes care of that demon bird!   10/10

Binoculars

Level 1: Quite useful if you want to see far away platforms or hidden flowers... 8/10

Extra optie

Level 1: With this you can choose 4 bonuses instead of 3.  I think 3 is enough, personally. 5/10

Level 2: You can choose 5 bonuses.  Hm. 4/10

Level 3: To get 6 bonuses. 3/10

Ice Age

Level 1: Changes water into ice for a while.  Useful, but you need to be quick! 7/10

Attraction

Level 1: The flowers will bend towards you.  Nice, but an extra jump works too. 5/10

Jump Aiming

Level 1: These goggles will tell you exactly where you will jump.  Very nice! 8/10

If I were to choose 3, I would pick:
Scarecrow, Extra Life Level 1, Higher Jump Level 1.