Some beer styles such as hefe weizen are suppose to be cloudy. Haze is caused by a shortened protein rest, high grain temperature, incomplete conversion, incomplete hot break, bacterial infection or by excessive sediment that has been stirred up. Floating things are most likely yeast and may be perfectly normal depending on the stage of fermentation.
Follow proper mashing techniques and keep sparge temperature down. Several finings can be used to help reduce or eliminate cloudyness and haze. Longer storage time in the fermenter and bottle also helps drop the yeast out of suspension and packs the sediment. Always watch your sanitation procedures throughout the process.