If you're looking for a good disk de-fragmenter,
http://www.auslogics.com/en/software/disk-defrag/ would be the way to go. Highly recommended. Works mostly in minutes, not hours.
Now on another note, I'm having a hard time figuring out what has happened to your computer.
You're saying that after installing SP2, there's about 130Gb of space that could be freed, the original installation of Vista? Service packs are not new installations, they are just a collection of all the Windows updates that have been released to that date. There are also some tweaks and other stuff, but by installing a service pack, you're not getting a new installation, just your old installation patched with the latest updates.
Only thing that comes to my mind is that you've installed Vista SP2 on top of your old install, which will make an "Windows.old" folder to your C - drive. If this is the case I'd still highly recommend a total from the scratch re-installation of Windows. Be it Vista or Win 7, but seeing that Windows.old folder in someones computer always grinds my gears
For Process Explorer, I've used it a couple of times, but usually it's a bit HC for finding out the simple stuff. It does come in handy from time to time.
I don't have too much experience when it comes to tweaking the page files, but I'd still say that you have something wrong with your computer. Ten 220Mb files equal 2,2Gb, which should fit in your RAM quite nicely.
Page files are used when you run out of RAM and the computer starts using the hard drive as an extension to your RAM. I'm glad that you got it working, but there is a downside to using page files. Using the hard disk as a RAM extension makes your computer run really slow and it gets even worse if your page file is located in your system disk.
As I said, I really don't know much about this issue, but maybe someone with more experience can help you here. All I know that there should not be much need for page files in new computers with 6Gb or more RAM. That statement is true in general use, which this isn't, so as I said, I really don't have enough experience to comment about this any further.
Janne