The IP address range can not be changed for the Mobile Hot Spot on your Droid 2 Global.
It appears that after Motorola rolled out the Gingerbread 2.3.3 update to DROID 2 Global phones on October 20th (when I received my update at least), you can now specify an IP address range to serve addresses from the 3G Mobile Hotspot app.
Just thought some might be interested.
So I am faced with a similar problem. I need to change my IP address in order to log onto a wifi network here in a hotel (where I will be spending the next four months). But I have no clue what I need to change my IP address to in order to get connectivity without conflicting with another device on the network. I have no clue what also needs to be changed (and what to change it to) when it comes to gateway, netmask, and DNS 1 & 2. Any information on this would be awesome! Thanks in advance.