Test cricket is the ONLY cricket... none of this one-day nonsense ;)
Once you know the rules (easy* ) and start to understand the strategy (hard) then test cricket is fascinating and pretty exciting!
* The easy rules are easy, then there about a thousand weird rules that hark back to ol' England. You take "tea" for example. Though my favourite is that if a ball is damaged or goes missing in the middle of a game, they go down to a kind of ball library and choose other balls that would be in similar condition (ball condition is extremely important and plays a major part in game strategy). Then both team captains must decide which of the candidates should be used.