For the brightest light output for the high and low beam you will have to do more than better bulbs. The problem is the stock wiring is restricted and can't support a good bulb to its full potential. The BEST thing to do is run a relay system and run higher wattage bulbs. Even better if those headlights you got are e-code specs. Then you'll have a clean cut line on the road. I did this on my mk4 jetta and it made a HUGE difference. Its not that hard to source and build the relay harness either. There are tons of info on it all over the web. I plan to do it to my R when I get new headlights...if I don't give in and go for retro fit setup.
Shoot me a PM and I can send you some links I have saved at home.
I don't have the bulb types off hand so I can't help you there. As far as t he fogs though people have done the HID drop in before. There was actually a thread not too long ago about it. From what I read, consensus is that, yes, you can do it BUT the out put (as far as visibility) wasn't that great because our stock fogs are aimed low and don't have a clean cut off. But if you're doing it for looks then heck yeah!