Looking at the specs you show for your computer, I see it has only 512 Meg of ram. This is marginal for installation of Mint 7 main edition. Some people get it to work and some don't.
A trick you can try from the live CD desktop is to open Partition Editor in the mintMenu and partition the drive before you begin the installation. The minimum partition scheme would be 512 Meg for swap and 10-12 Gig, Formatted ext3, for / (root). This allows the installer to use the swap space as virtual ram if needed.
if you read this thread, you will get a lot of information about installation and partitioning.viewtopic.php?f=90&t=11872
If you need more help, don't hesitate to ask for it. There is always some one around to answer.