To 1: On many comments of people.
Such as? I'm willing to bet you don't have anywhere near the qualifications to evaluate their validity of the comments these people are making. My guess is that your statement is based on the naive assumption that if you can buy a more powerful microcontroller than the mega168 from digikey for a few dollars more, that means you could easily make an Arduino around it for a few dollars more?
To 2: It seemed that on the net are good documentations on arduino, and as a beginner project it seemed appropriate.
It is appropriate for a beginner project. What you are asking for would not be. People getting started in microcontrollers don't need huge code space.
Look at it this way: you don't buy bicycle and then complain that you can't use it to go 80 mph down the highway. If you want an inexpensive, easy way to get around without walking, you buy a bike. If you want to go 80 mph down the highway, you buy a car. You definitely don't get pissed at the bicycle makers for not making cars. You picked the product you thought would serve your needs best. If you made the wrong choice, you have no one to blame but yourself. Don't try to make yourself feel better by playing the victim and saying that the Arduino sucks; the Arduino is great when used within its intended scope.
To 3:
Why should I need delays? pulseIn itself "has a delay", or not?
Edit: Well it works, somehow. But do not quite understand it yet...
How should I know why you need delays? This is where you actually go and troubleshoot your own application. Maybe there's a bug in pulseIn(), but that's hardly a reason to condemn the Arduino hardware or mega168 in general. More likely, you have no real understanding of how to use pulseIn() properly, and I'm guessing you don't really understand how your IR receiver works, either.
At any rate, you seem to be quite quick to blame everything but yourself for the problems you're having, which is a terrible attitude to have when you're trying to learn how to do something. You should approach things with an open mind and an attitude of "what am I doing wrong/how can I make this work" rather than "why doesn't this work, it must be broken/defective". If you had the former attitude I'd be much more likely to actually care about your problem and devote some time to trying to figure it out.
- Ben