I'm still having the same problem as before! About 8-9 minutes into the bsp process a windows message comes up and says that there isn't enough virtual memory left and while it is increasing it, some applications may be denied.
Soon after that, I get a message in jk2radiant:

(Output buffer full: clearing it)

completed.
Run time was 0 hours, 9 minutes and 45 seconds

After this, there is no .bsp file. Is there a way i can tell windows to increase virtual memory before this happens? What is virtual memory in the first place? I have 256 megs of ram, it isn't too much but my little map cant possibly use up all that in the first place?

Virtual memory is the what windows uses when you run out of memory. AKA your harddrive. It's much slower than your 256 megs of RAM. You can increase your virtual memory in control panel/system/performance. BUT What I would do is find a memory freeer(word?) like Ram Idle. (www.tweaknow.com) It will free memory if it gets below a certain point. Or the alternative is go buy some ram because it's really cheap now. 512 should be fine.