Use a program like winzip or winrar. Here's how I do it...

1) make a folder on your desktop and drag all your images you want to "zip"/compress into it.

2) Right click on the folder and select "compress and email" or something along similar to that.

It should then make a new zip icon on your desktop with the same name as the folder your made. Then go to your email account, and send that file. The reciever will be able to download the file to their hard drive and then open it from there.