I most likely played it in the late 90s (1997+). It might have been the early 2000s as well, but it's less likely. My computer at the time was running Windows 95 or 98.
The game came on a CD with a washing detergent (probably Skip, a brand by Unilever) in Greece but was in English, and likely other languages, so logically it was available internationally. It was either included with a big box of the detergent, or perhaps you had to mail some coupon from the box.
From what I remember of the game itself, the theme was washing machines. I think you controlled a blond boy who moved around a pseudo-3D environment, displayed at an angle, so that the left arrow key made him move northwest, up northeast and so on. I think jumping was not possible, so you had to climb up stairs or fall down in holes to reach other heights.
There were collectibles, but I'm not sure what they were. I think some were diamonds and some others were Skip boxes. There were probably some washing machines as well, either enemies or background. I think there were also whirlpools you had to avoid, and perhaps there was a dog following you (but I could be mixing it up with another game).
The challenge of the game was to find your way around the level so that you could grab all the collectibles, while avoiding enemies and hazards. It probably played similarly to the modern Captain Toad game.
Other software on the CD
The CD also contained a program about the detergent, mostly running on Quicktime, if I remember correctly. It had adverts for the detergent from all over the world and perhaps tips for washing clothes. I specifically remember an advert from a South American country (probably Brazil) that was a bunch of people singing and dancing at a garden party (while washing clothes, of course).
I'm wondering if there is any way to find this game in the present age.