Hi
I've heard people getting thier visa's within about 10 days but saying that there are still peple getting it in the 12 weeks period they state. So I guess if your lucky and if all your docs are in order then it may get processed quicker.
In regards to the fingerprint situation, you don't have to travel to Islamabad, this is all done by Gerrys offices on behalf of the embassy. Visit
http://www.ukvacpk.com and scroll through the different pages , it states the various Gerry offices in Pakistan and how to process your application with them etc. They also take the digital photo of the applicant and fingerprints at the time of applications, check the timing for submissions as they only acccept upto midday.
Good Luck