Saahil
School Cricketer
Hmm..The Mobile I use..??
Oh no no, don't go for the 5800, if you're gonna buy a new one, get the 5530 Xpressmusic.
Well, its basically that 5530 is the next and better version of the 5800. Better and refined UI, much more stable, and some better features as well from what I heard. Have a look at gsmarena and read the review of the 5530.
The camera should definitely be better than the 5130. If I remember correctly the latter was 2MP whereas this one is 3-3.2MP.
What's your budget? There's a whole new host of Android phones coming to market as well.