What does "using close to 3GB of Virtual memory" mean exactly? Is this the total size of the allocated memory? Or the sum of the allocated memory of the applications? VSIZE? RSIZE?
Does the computer work? I guess it does. So just quit Activity Monitor and let the OS do its job. Unless you really know how things work (in which case you would probably not be posting stuff like this ;-) ), the chance you can improve them is pretty minimal.
Just for your info, this is what things look like on my MBP with 2GB RAM with some 11 apps running (plus the system of course).
Code:
Processes: 88 total, 2 running, 3 stuck, 83 sleeping... 356 threads 17:36:35
Load Avg: 0.65, 0.56, 0.47 CPU usage: 7.56% user, 10.67% sys, 81.78% idl
SharedLibs: num = 12, resident = 57M code, 276K data, 4024K linkedit.
MemRegions: num = 15325, resident = 603M + 20M private, 847M shared.
PhysMem: 252M wired, 789M active, 571M inactive, 1612M used, 428M free.
VM: 12G + 368M 696345(0) pageins, 910637(0) pageouts