yes and no
Icons are actually .BMP files re-named to .ico
and are usually square with a resolution anywhere from 16x6 up to 256x256 (vista). 32x32 or 64x64 are generally good enough - you can use windows paint .... or many graphic proggys have ICO options
or A dedicated proggy such as IconWorkshop (there are lots out there)
or if you just want one or two ... use one of the free online sites
http://www.rw-designer.com/online_icon_maker.p hp
quality is a big issue ... a good pikkie isn'y always a good icon .... best way is to give it a try