I was trying to boot the Trinity Rescue Kit without having to burn a CD. I never did get it to work, but I did get the Ubuntu ISO to boot.
Method 1 (didn’t work for me)
Step 1. Download the ISO File. Save it to a directory where you can browse to it.
Step 2. Browse to the downloaded file. Right click and choose “Open with ‘Archive Manager’. (This is for linux. You could use 7-zip in Windows, maybe WinZip).
Step 3. Insert the USB Drive; notice where it mounts the drive. For me it was at /media/disk.
Step 4. Extract the ISO file by clicking the Extract button in Archive Manager. Enter the path where the USB drive was mounted for the destination path.
This didn’t work for me. I am assuming there is more to it than just copying the files onto the disk.
Step 1. Download UNetbootin.
Step 2. You need to make the file bootable. I ran chmod +x unetbootin-linux-299.
Step 3. When I ran it the first time, it told me that it needed mtools installed. This was easy to install with: sudo apt-get install mtools
Step 4. Run it from the terminal with ./unetbootin-linux-299
Step 5. Choose the diskimage and pick the iso file.
Step 6. Then, click OK
This worked on Ubuntu, but not on TRK. When it booted into Ubuntu, it gave me a UNetBootin boot menu, and then it booted all the way into Ubuntu 8.10.