15 min works ok for entries daytrading, obviously look at longer time frames as well to identify significant levels.
The spread is 1.2 pips at my broker in the EUR which is pretty good IMO. One of the great things about the forex market is that there is alot of volatility - providing many trading opportunities. Being the largest market in the world it is also extremely liquid. I just trade the London/New York overlap session - but it's cool that it's a true 24 hour market 5 days a week.