kluster

i have a 500gb hard drive that lost a partition(displays it as raw), the second partition works well with no problems, it is just the main partition that went bad. it has very important information that i would like to recover from it. i ran testdisk and it says the mbr is bad. how can i recover it. i ran active partition recovery on it and it displays the root file structure but when i try to open it, it just hangs. i believe it has bad sectors. is there a way to bypass them and salvage data off it? thanks!