Gatech's ftp is a nice place to download ISO's for many distros. And their connection is REALLY fast. Im on 2mbit cable, and they max my connection all day.
I download all my ISO's from this server.
As far as burning the ISO's, I use XCDroast to burn them(assuming your running linux).
If your not using linux... I guess you wouldn't be here
Anyways you would have to install xcdroast, and click on the setup button first and configure everything. It's all GUI, so it's pretty easy. You'll have to set up a directory for xcdroast... it will be on the HD Settings tab labeled as "temporary image storage directories". Simply map that to a pre-existing directory, or mkdir a new directory from the command line and add that directory to the list. After you have done that save the setup config. You need to move your ISO's to the image storage directory you specified, and when you start xcdroast again, the ISO's will be listed.
Click on the write tracks button on the left, and click on the layout tab... select the ISO and click add, then go back to the write tracks tab and click the "Write tracks" button at the bottom and it will begin burning your CD.
I hope this helps...