Photobucket rules all. Aside from Ridemonkey of course.
Seriously it is SO easy, it resizes pictures automatically (if you just use the freeware). If you upgrade you have the option to do either. It does not make your guests "register" to view your pictures.
i use a Site call SMUGMUG and will be dificult to be happier. I'm a lamme computer person, so is perfect for me everything is right there at your finger tips.
Here is my own gallery as a example the sistem is so cool you can even upload fotos from your movil phone just by "calling the site" (i think is even a patent exclusive feature) so others can see what you are doing right when is hapenning, very useful features for reporters and i guess for events like interbike when you want to be the first to have a picture of some cool bike on the net..
is not free but the advantages are so much i don't really care
i have both photobucket and imageshack.
i have a bunch of pics on photobucket and its a good service, but limited in size
imageshack is unlimited but you cant orgainze them into subgroups (or i havent figured it out yet)
-you can upload from your phone
-gives you url, tag, img tags
-you can make albums and sub albums
-premium memebership $20/year - I think unlimited pics
-on the site you can upload up to 19 at a time (you have to click browse for each picture
-if you download an uploader, you can copy up to 20 of files into it (with out clicliking browse each time for the next picture