Well, web pages are usuallly pretty small photos with low resolution so just about any lens will do the trick.
As far as birding goes, there are people like NHL who will give you the lowdown on birding lenses.
Birding lenses tend to be long, fast and expensive.
You might want a generally nice walk around lens like the Canon 17-85 image stabilized. The 17mm is really nice on the wide end. Other than for birding, you might find yourself taking 85 percent of your shots with the 17-85.