fire emblem radiant dawn

ok, so I downloaded this game (from here) so I could play it on my dolphin emulator(first game I try on it) and i am having a hard time getting it into the right format. I am trying to get the file into a .iso file (it is currently a .rar) but cant seem to do it. i have winrar and i am trying to extract the file but every time I try I get a error message which says:Checksum error in hz-ferdv 101.iso. file is corruptThis is followed by another error message saying: Unexpected end of archiveSo basically I need help getting this file into the right format so it can run on the dolphin emulator.I'll admit I am new to Wii emulators and have only dealt with the VBA emulator, which I think is much easier as files come ready to play when downloaded. So ya, any help you guys could give me would be appreciated and thanks in advance.

Looks like the ISO file is corrupted, maybe it didnt download properly.
You will have to re download the ISO again.
Use IDM (Internet Download Manager) to download, its very helpfull and it allows pausing and resuming and its really fast compared to your browser download managers.

make sure you're using the latest version of winrar, the algorithm it uses has changed recently. If that doesn't help then the file is corrupt and needs to be redownloaded. Use a download manager as suggested by dark infernape.

ok, thanks guys your suggestions worked perfectly. It's nice to a helpful active forum to go to in times of trouble.