I have been playing online for over 4 years. I have played at (in rough order) Planet, Paradise, Party, PokerStars, Full Tilt, and Bet365. Probably one or two more if I really thought hard.......

In a nutshell: the best (softest) ring games are at Party, the best tourneys are at PokerStars. I love Paradise's software and the "game feel" there, but the ring games are tight. FullTilt has a great bonus on your first buy-in but I found the low limit games there to be unexpectedly tougher than other places.

I think the best bang for your first buy-in buck is probably at Party. They have micro-limit tables set aside for beginners. In those games, play tight, and do alot of check-calling on the river when you have a hand because 2 times out of 3 this is read as weakness and your opponent will bet a)on a bluff or b) bet a weaker hand.

Make sure you take advantage of a sign-up bonus and other perks (free tourneys, etc.) that are offered to all new players.

Good Luck, and FYI, in 4 years, I have NEVER had a problem with ANY of these sites.....