As far as I'm aware, you can delete multiple photos by hovering the pointer over a picture until an options box comes up, then click the little box next to the picture's title. When you've selected the ones you want to delete, go to the bottom of the page and select "choose action". That should bring up the option to delete all selected photos.
As for resizing, if you select the picture you want, then hover over it until a toolbar comes up. If you click "resize", a box should appear and you can select the size you want. Another way is to hover the pointer over the picture you want to resize until the options box comes up, then click on Edit (in the blue bar). It should take you to photobucket's editing suite. Once there, you get a list of options which can alter your photos. To resize, click on Adjustment, and then resize. This way gives your more choice over the size you want, including custom resizing. When you've finished, click Save, and it should take you back to your album.
The editing suite is also where you can tinker with the colours, add borders, and use a number of different effects on your pics. The interface is a little different than it used to be, so I might not have everything quite right, but that's how I resize my pics.
Hope that's of some help!
