The history is a list of places you've been to by typing in the address (as opposed to following a link) - if you like somewhere, bookmark it.
The Temp internet files are local copies of pages you've visited - unless you've got God's own internet connection, it will always be slower to get the files from the remote site than from your cache. These files should be automagically cleaned out by your browser when the cache is full. The cache size is defined in the options menu.
Hope this makes some sort of sense...