reaction speed in finder & bookmark in firefox

hi ppl,
i'm still new in mac world and i would like to ask u for two advices
1. is it normal that in finder /in culumns mode/, if i'm clicking from left to right always to subfolder, for example, i start places - my mac, then pictures where i choose for example folder party where are cca 30pictures of total 150mb and the reaction time to pop up the file names on the right is between 3 to 5 seconds?! it happends also by other folders and subfolders with different sizes,
otherwise my mac book pro 15, 2.4, 4gb ram runs ok, quiete stable, but after skipping from windows i wasn't expecting this kind of speed by simple using of finder...

2. i like to use firefox and on win i really liked icons instead of sites name on bookmarks toolbar, well on mac i cannot find this option, do u know if it is even possible to save site on firefox on mac as icon?

thanx a lot for your comments,
xxx