Whether he stays here or returns to pak is something that you will both have to decide for yourselves. Both have pros and cons and most people have posted good sound advice already.
With regards to applying for your spouse visa following your nikkah - what kind of visa is he currently on in the UK? You say he's 'settled' but that can often range from a variety of different immigration statuses here. If he's on a student visa then he'll have to prove that he can financially support a wife in the UK (bearing in mind that he can't work over 20 hours a week) which is quite hard to do on a student visa. If he has ILR or a work permit then let me know and I'll advise further.
i dont kno abt his current visa, its of working visa i guess, i'll ask him n will tell ya, thanks foe help :)