Some webpages have a link to a printable version which gives correct printing so always watch out for this. If you use Print Preview you will be able to see what you are going to get before you commit it to the printer. I sometimes drag the cursor to select the text and pictures in the main body of a page then copy and paste into my wordprocessor but if you want it with the minimum amount of work then follow Al94's advice and print landscape.
Yes as above, reduce margins or from printer properties select "Scale to fit". This is not a fault with your printer and most printers do the same. It is to do with the way that websites are optimised to fit the screen and is controlled by pixels.
Printers work on DPI [Dots per inch] and the two don't always match unfortunately. I have a Canon printer which places an Icon on the IE6 toolbar named "Easy-Print" clicking on this will automatically adjust the display to fit on the paper without missing anything out. j.