What will happen this 6 February if they will decide to regulate ICOs and Cryptocurrencies, taxing them?
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Do you think is better to buy-in after the crash at cheaper prices?
While there are many important ramifications that may or may not take place were such events to happen, such as taxes, market crashing, limits to amounts individuals can invest... when you say "if they decide", the "they" means something different to everyone in the international forum.
I'll interpret that as the government or governing tax and securities commissions, in each country. We know that many country governments have made moves just recently regarding cryptocurrency to the outright ban by the Chinese, yet many crypto firms operate there so to what extent that regulation is still unknown, the same for South Korea threatening to shut down all crypto exchanges to now placing firmer regulations on allowing compliant exchanges to remain operating, and almost all are placing tax implications on specifically cryptocurrency trading where there was not a firm rule before.
With all of this going on and mostly due to your concern over it, since we all have to weigh our own risks and some are heavily invested while other are not, I would say it is better to wait simply because it is 4 Feb today, and you are wanting to know about after 6 February.
So without giving advice, answering your own question with the concerns that you stated... it seems you might want to wait. At the same time it will take a period of time for new regulations to take effect, however it is wise to be prepared and that's only a matter of days now. Better safe than sorry maybe.