I agree with Halkun. If you need to convert between formats,
http://www.irfanview.com/" TARGET=_blank>Irfanview is by far your best choice. I've used it for a fair amount of time, and I don't really have (m)any complaints. It supports a *ton* of formats (lots of plugins), a couple languages, and, best of all, it's free.
[This message has been edited by Srethron Askvelhtnod (edited June 01, 2001).]