Since I am not a H2 Hummer owner, I have not know about the H2 headlight set up, but if they are the 6024 like on the H1, Sylvania makes a HID headlight that replaces the 6024 headlight. There are two versions of them, the first generation sucks and make sure you do not end up with them or you will not be happy with them. The second generation that came out this mid summer are much better, cost is about $400 I think.
The Silver Stars bulbs are about the next best thing for the money, you get a little more light of them, but also a better color. I have the X2020 HID from Sylvania on the Suburban and the highbeams are the Silver Star and side by side to the HID, they are great IMHO.
Allan Madar 93 Red Hummer Wagon
www.redhummer.com
Allan Madar - RedHummer.Com
93 Hummer - Diesel Wagon