I think the misconception here is, I don't close the files I work on. The project is already open. It's pointless to close files and keep application open. I keep files open, too. And I don't know about you, but I tab much faster than that. Maybe because I have more practice? I sometimes use the mouse to click on taskbar icons, too.
Now... the hard way... I currently have Windows Explorer, Internet explorer, Pelles C and my media player open... I want to go to Pelles C and do a little coding... WIN+TAB, open the application rolodex... ~1 second... tab tab tab tab Ah there it is...about 4 seconds... Pelles C is on screen... File-> Open, path to project directory, pick project file click OK... about 8 seconds... ready to code in a mere 13 seconds...
I reboot about once a month, and contrarily to popular belief, we don't go through start menu and open everything on boot. I open things when I use them the first time, THEN I leave them open. You have to open and close things AT LEAST as many times as I do.
Now lets really load it up and do this your way... enable the swap file, managed by windows... reboot...
Open Windows Explorer, Internet explorer, Media Player Classic, Email, FTP Client, MS Word... about 1 minute in... starting to get slow guys! Drive is thrashing like crazy-- The Gimp, Irfan View, Magic ISO, Burn Aware... really thrashing now... almost 2 minutes to open all that stuff.