All this while since 2008 i was happily using Hardy on my laptop but since the official support is getting over soon i preferred reinstalling from fresh. I was thinking to install 10.10 but today only i came to know that my CD drive is nomore. Thanks to USB boot, i managed to have get Lucid working on my ACER 5920 laptop.
The only place where i was stuck at is the mic was not working after googling i came to know that my Codec: Realtek ALC1200 and solution to that is adding 2 lines in my alsa config file.
$sudo nano /etc/modprobe.d/alsa-base.conf
options snd-hda-intel probe_mask=1
options snd-hda-intel model=auto
Restarting ALSA (sudo alsa force-reload) and also checking alsamixture 2 confirm if mic in muted.