I figured out the problem. It was because I was using Internet Explorer. Ugh. Problem fixed now.

ok its just an offer

Hmmm. I might. Let me see what I can dig up online first. Maybe I can find out whats going on.

you want me to do it for u? i could give u an exe to run that means i can come and do it for u using software called teamviewer

if you do go to

http://www.teamviewer.com/en/index.aspx
then bellow the giant green start full version its free button click the link that says
join remote control session, run it and then send me the two codes it gives you. as long as you have that program open i can then come and help you. when we done just close it and i cant access again. you can see what i am doing as well

That's the same one I downloaded. For some reason it's actually opening the files instead of showing a .jar file.

http://assets.minecraft.net/12w07b/minecraft.jar
use this one its the snapshot, think u downloaded client one or something

I did it with 7zip. Still can't find the .jar file. :/

ok using winrar or 7zip open the file and then you have your .jar, its currently compressed to make it smaller to copy over internet

win rar and 7zip are software

It didn't give me a .jar file though. It gave me a .zip

if you are pc then open my computer then in the bar at the top type in %appdata%
then click.minecraft, bin then delete minecraft. jar and paste the one you downloaded there, run minecraft as per usual and you are on the snapshot

ok mac or pc?