Well, that's intriguing! Good rule, I think. Who publishes rules for blitz, pfren? Is it FIDE or another body?
Could I have claimed a win here?

If the opponent makes an illegal move, you should stop the clock and claim a win. If the opponent is difficult and the arbiter does not agree and gives the opponent extra time, so be it.
This only goes for blitz games. With regular time control, illegal moves should be taken back.
Lacking time, I simply press the opponent's clock immediately when something happens most of the time. If you caused a problem it is not my move, and you fix it.

Then all hell breaks loose because my opponent then claims the win due to the fact that taking the king is, in itself, an illegal move!
It's perfectly legal to capture the king and win like that, according to the rules of blitz.
Not in regular time controls, though.
really? sounds like a fun way to win.
OT, I would tell the guy or girl that what he did wasn't good sportsmanship and if he pulls anything like that again, you won't play him anymore.

Mind the country... Capturing the king loses in itself in Blitz, but this doesn't always have to be the case.

If the opponent makes an illegal move, you should stop the clock and claim a win. If the opponent is difficult and the arbiter does not agree and gives the opponent extra time, so be it.
This only goes for blitz games. With regular time control, illegal moves should be taken back.
Lacking time, I simply press the opponent's clock immediately when something happens most of the time. If you caused a problem it is not my move, and you fix it.
That's pretty much the way it works in South Africa too.
For Blitz, on illegal move, stop the clock, and claim the game. If you capture the opponent King, you lose.
Hello trollpumpa. I had a look at the FIDE site and I see that you are right.
" Leaving one’s own king under attack, exposing one’s own king to attack and also ’capturing’ the opponent’s king are not allowed."
This is what article7.4b says:
" ...... for the first two illegal moves by a player the arbiter shall give two minutes extra time to his opponent in each instance; for a third illegal move by the same player, the arbiter shall declare the game lost by this player. However, the game is drawn if the position is such that the opponent cannot checkmate the player’s king by any possible series of legal moves."

Speaking of time related losses, I was playing an upper 1800, even though he is higher rated we go back and forth. He was easily winning but had 5 secs on the clock. He moved and said "checkmate!" I thought it was mate for a second, then saw an escape square for my king. I moved, and he flagged with multiple mates in 1.
I was playing an over the board chess match yesterday, blitz competetion, 10 minute on each clock. Anyway the problem i am having is that i feel like i was cheated... Now on the last game i was down on time, but in an entirely winning position, anyway i was close to checkmate, opponents position hopeless, only a few pieces left on the board. Anyway the problem i having,ok, imagine this, me with 10 seconds left on chess clock, only a few moves of checkmate, then oppenent plays illegal move, presses his clock and as i correct him, i loose valuable few seconds off my clock, and eventually with like i move of checkmate loose the game on time, could i have claimed a win at the moment my oppenent played illegal move wasting my time, if so do i stop the clocks or just leave my clock running. please help!