I have 2 partitions on my Compaq laptop. Windows 7 is installed to one and Ubuntu 12.04 is installed to other using a usb stick installer.
What I noticed is whatever I do (opening a tab in browser, running a new program) is much slower and makes too much hard disk noise on Ubuntu. Also the boot time is longer on Ubuntu.
My Windows partition is ntfs and it is 100 GB. Ubuntu partition is ext4 and 8 GB.
I have AMD Turion 64 cpu, 2.5 GB RAM and NVidia 6100 graphics card.
EDIT: Adding the output of df -h
Filesystem Size Used Avail Use% Mounted on /dev/sda6 8.1G 5.7G 2.0G 75% / none 4.0K 0 4.0K 0% /sys/fs/cgroup udev 1.2G 4.0K 1.2G 1% /dev tmpfs 245M 1.4M 243M 1% /run none 5.0M 0 5.0M 0% /run/lock none 1.2G 13M 1.2G 2% /run/shm none 100M 16K 100M 1% /run/user