I've tried installing Ubuntu 11.04 along with windows 7. But I got problem in allocating the drive space for installing Ubuntu. I've 160GB hard disk partitioned into three drives. D and E drives are almost full with data and backups. I've about 35 GB free in C drive and win7 is installed in drive C. Please help me out in allocating drive space for dual boot.
You can only create four primary partitions on a hard disk. In your case, you already have 3 primary partitions. So, you will need to create logical partitions from now onwards. Just to clarify, you can create 3 primary partitions, plus as many logical partitions as you want.
Ubuntu requires minimum two partitions to work. These are "/" and "swap".
When installing Ubuntu, you will have to create two logical partitions. The Ubuntu installer will give you the option to do so.
So, make some free space by moving as many items as possible away from E to some other place. Then, go to Control Panel. Click on "View by Category" in the top right. Then go to Systems and Security > Administrative Tools > Computer Management > Storage > Disk Management. Right click on E and then "Shrink Volume". This will create some free space for Ubuntu.