Is it feasible to disable the page file while running 4GB of RAM? (3.5GB seen by windows in XP 32bit)
No, it's not feasible in any modern OS.
Best thing to do in XP 32-bit is to just set the pagefile to a static size of 4GB, that way it can't fragment at all. Make one on your boot drive, and one on your fastest other drive(s), Windows will automatically use the fastest.
Want to bet on that? A number of newer games have trouble with 32-bit memory limits (STALKER, Supreme Commander, The Witcher). 4GB of total memory usage is easy to hit with multitasking. My general programs that I keep open take about 2GB, if I want to open a game, it takes the rest of that. If I'm doing anything particularly memory intensive (video editing, graphics work, compressing files), I can't game without closing the application.
Thats only due to the 2gb user space for progams in Windows which would STILL exist in a 64bit environment unless the game is coded for 64bit whicih SupCom is not.