You can enlarge most of the text by selecting 'View','Text Size' and 'Largest' off your IE toolbar, though you'll want to change it back again to carry on browsing.
Unfortunately this doesn't work on the fiddly graph, so the only option is to cut and paste, though you can just cut & paste the graph rather than the whole document (in case anyone's doing that....er, like I was)
OR try Belfield Tide Plotter 2003, which is pretty spiffy.
www.tideplotter.co.uk . It costs £9.95 :pity_party: but I reckon it's money well spent cos it's more portable.