SYSTEM SLOW UBUNTU 11.10

If you log in as a different user, is it the same?

Could you run command
    top
to see if a process is using much of the CPU

top - 04:24:28 up 23 min, 1 user, load average: 0.17, 0.26, 0.34
Tasks: 142 total, 3 running, 139 sleeping, 0 stopped, 0 zombie
Cpu(s): 6.6%us, 3.3%sy, 0.0%ni, 90.1%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1283356k total, 1096972k used, 186384k free, 84696k buffers
Swap: 467964k total, 0k used, 467964k free, 484708k cached

Swap: 467964k total, 0k used => you have no memory issue when you launched top
Mem: 1283356k total, 1096972k used => but you are close to use all RAM
Perhaps sometime you use too much memory, and your PC has to move memory between RAM and HDD (swap). I don't know if Oneiric uses more memory than Natty. Memory usage is a point to check when PC become unresponsive.
It seems you have really no CPU issue. 6% is very few.

Sorry, I forgot a last point. Could you run command
   df
to check which percentage of disk is used. Unix becomes slow when disk reach 90% of true space.

Run the df com and got the following details:

Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda6 9242552 7440828 1332220 85% /
udev 634676 4 634672 1% /dev
tmpfs 256672 752 255920 1% /run
none 5120 0 5120 0% /run/lock
none 641676 200 641476 1% /run/shm
cgroup 641676 0 641676 0% /sys/fs/cgroup
/dev/sr0 502518 502518 0 100% /media/VCD

regards
Abdul

Do you have only 4GB for Ubuntu ?

Can you give the output of:

df -h

Instead, its easier to read

Filesystem Size Used Avail Use% Mounted on
/dev/sda6 8.9G 6.8G 1.7G 81% /
udev 620M 4.0K 620M 1% /dev
tmpfs 251M 756K 250M 1% /run
none 5.0M 0 5.0M 0% /run/lock
none 627M 320K 627M 1% /run/shm
cgroup 627M 0 627M 0% /sys/fs/cgroup
/dev/sr0 491M 491M 0 100% /media/VCD

Looks fine. Is it the same slowness as a new user too

Filesystem Size Used Avail Use% Mounted on
/dev/sda6 8.9G 6.8G 1.7G 81% /
udev 620M 4.0K 620M 1% /dev
tmpfs 251M 756K 250M 1% /run
none 5.0M 0 5.0M 0% /run/lock
none 627M 320K 627M 1% /run/shm
cgroup 627M 0 627M 0% /sys/fs/cgroup
/dev/sr0 491M 491M 0 100% /media/VCD

Thank for your query.This is the out put for df-h.Looking forward to reading your comments and suggetions.
Abdul

Sorry I haven't created any new user yet.Should I do it now?

Sure, then log in as the new user and test