The BEST institute in your area would be National University of Sciences & Technology aka NUST. It has ALL kinds of engineering disciplines BUT u'll get admission only if u r top of the line student and have an IQ high enough to top their entrance test. So, your FIRST preference should be NUST, as it would be close to our home. The field of study depends on your interest.
Electrical Engineering (Power or Communications)
Computer Engineering
Mechanical Engineering
Mechatronics Engineering
Other than that, they offer Aerospace Engineering in their Risalpur Campus.
Your second preference SHOULD be COMSATS Institute of Information Technology, Islamabad which has REALLY grown in reputation lately. You should be able to get on the merit list of this institute.
Your another second and final preference should be GIKI (Ghulam Ishaq Khan Institute of Engineering Sciences & Technology, Topi, NWFP) which is a private institute located in the remote city of Topi, which is 30km from Attock I guess. It is NECK on NECK with NUST but again, u'have got to be best to adjust with the rest. People from all over the Pakistan & overseas Pakistanis live their in dorm rooms. It is THE next-generation institute.
Other than that, there are no topline institutes for Engineering in Islamabad/Pindi cities. But the reality check is that, it doesn't matter anymore which university you get into. If you know how to get the work done for your employers, they will hire you. They wont even bother to see your resume. The thing is that, in Pakistan, a big approach, jaan pehchaan, and a little bit of luck all combine to guarantee u a job in Pakistan. Employment in Pakistan is unfair system.
Still, NUST & GIKI have prestige. While CIIT should be your second preference. GIKI is kind of better than NUST cos NUST relies on prestige instead of their professors & students.
I myself am a Bachelor of Science in Electrical Engineering (Communications) from NWFP University of Engineering & Technology, Peshawar. I too lived in a hostel & am going for MS. Alas, there is no UET in Islamabad/Pindi area coz people of Lahore & Punjab prefer UET, Lahore over NUST or anything, people of Karachi prefer NED UET over PNEC(a NUST college in Karachi). Still, if u cant get into NUST or GIKI. COMSATS IIT is the way to go.
Every field is in most demand. If u can excel or master ANY field, it'll pay u off in hefty sums. So, go for anything that interests u.
If u need more info about engineering fields. Let me know.