No, not in most countries in the EU and UK. But the license the casino uses can have its own restrictions in offering online gambling to certain countries. So, if you experience an IP block when visiting the website, it's probably because you are in a country that the casino can not offer their services too.
If we are talking about amounts around 4- 5000€, Neteller and Skrill could be a fast and easy solution for you. Usually, the money is in your online account within 24 hours, and you can also have a very own card connected to your Skrill or Neteller account.
NetEnt, Betsoft, Play n 'Go, Microgaming, Big Time, and Red Tiger are probably the ones that rank highest over the most popular online slot machines these days. Here, it's a good idea to try them out in the demo version first, so that you find the games you like the best, rather than thinking about what everyone else is playing.
Card counting is a very well known strategy in Blackjack that has worked for many players to break the bank of casinos around the world. But this strategy requires tremendous concentration, and with today's number of decks in use, it is almost impossible to achieve this without practicing hard every single day on such strategies.