There's a known issue with Dell QuickSet (at least for me and some Studio XPS 1640 users), it seems that every time when I use the Caps Lock key to change from upper case to lower case and vice versa, weird stuff happens:
When renaming files, hitting the Caps Lock will quit the renaming process; it's as if you just hit the Enter key while you're using the Caps Lock key.
Another scenario is when you're messaging someone, writing an e-mail or posting on forums with a web browser, hitting the Caps Lock key will inevitably bring out other windows previously minimized in you taskbar or shift the focus of the window to other windows. Again, it's as if you've hit the Alt-Tab combination keys while using the Caps Lock.
I find this annoying at best, at first I thought my Caps Lock key is broken; searching around with Google didn't yield any potential solution to this problem.
But today, I discovered the root of the problem: Dell QuickSet; as strange as it seems, this program has been causing me much pain over the past few months.
This morning, I released my frustration on the Caps Lock key. I depressed the Caps Lock key for a brief moment (while clenching my teeth in frustration) and I saw my web browser window blinking rapidly (like pressing the F5 key in the Explorer window to refresh your file list etc), then I thought maybe the Task Manager will show me which application/service is consuming the most CPU resources while I'm holding down the Caps Lock key. So I brought up Task Manager, depress the Caps Lock key and observe the CPU usage for each processes.
Lo and behold, Quickset.exe and Explorer.exe consumes the most amount of CPU resources with the Caps Lock key depressed. Quitting QuickSet solves the problem, finally.
So if anyone's Caps Lock key is acting very weird lately, give this solution a go.