Thanks for the quick response amd64_man2005.
Since, I have no idea about mobile phones, I consulted some of my self-professed mobile geek friends. Getting an opportunity to give a lecture he told me about the virtues of Nokia phones and great service support you get with Nokia.
Then I asked him about Sony Ericcson. He started to say that Sony Ericson phones are not very good in build quality and key pad and all the stuff worn off quickly.
Because of curiosity, I asked him again about Samsung phones. "Dude, what will you do to get an accessory? even for a simple phone cover you will have to search a hell number of stores"
I am really confused now, so what is the truth? I like to think I am wrongly informed

I like to have more options.
Comparison of Nokia 5310 and 6300
My brother have 6300. He says it get hot too quickly and battery drains a bit more quickly than one likes. Otherwise, I think it was a perfect phone.
Keep your suggestions coming .
Alright, I have took a look at both the phones you recommended :
- Sony Ericsson W810
- Sony Eicsson W580
W810's display is 256K colors and screen size is 176 x 220 pixels, 30 x 38 mm
W580's display is OK. But it supports only 256K colors.
They are in my consideration for their great sound quality and music support. Any other options?
Thanks for the replies, keep it coming.