Spread the holiday cheer! (Or "change your avatar for the holidays")

[Hawkeye]

I tried to change my avatar tho this
[URL=][IMG]http://img508.imageshack.us/img508/2548/avatarbanjokazooierd8.png[/IMG][/URL]

but VG Chartz said it was't a supported file. How do I change it to a supported file? (probably JPEG becuase it is originally bitmap)