[ubuntu] Need to ReInstall Ubuntu 12.04 on my linux partition, but need to retain my files

view story

http://ubuntuforums.org – I had Ubuntu and windows 7 installed on seperate partitions on my laptop, well windows crashed, of course forcing a reinstall of 7, well after i installed 7 i no longer had the option to boot into my linux partion when i turned the laptop on, so i was just going to load up the live cd of ubuntu and do a reinstall, but i need to keep my files and i cant just copy them over using the live cd because it says permission denied can anyone help me get my files? or tell me how to reeneable the boot selection screen so i can just boot into the already installed ubuntu on my hard drive? (Hardware)