You can delete any unwanted profiles, programs, and data. I'd suggest a thorough scan-and-clean w/ at least a couple different spyware scanners, such as Ad-Aware SE Personal, Microsoft Antispyware Beta, the evaluation version of Ewido Security Suite, and/or Spybot S&D, an online spyware scan-and-clean w/ Trend Micro's Housecall spyware scanner, a thorough system scan-and-clean w/ your own resident antivirus, and an online virus scan from at least one of the major AV vendors, along with mebbe a vist to and runthrough with Microsoft's Malicious Software Removal Tool and/or McAfee/AVERT's Stinger, just to make absolutely sure no nasties are lurking in the system somewhere, then get busy and start deleting. When you've deleted all the applications, files and folders you want rid of, use a disk cleanup utility such as Cleanup4 or CCleaner, then defrag your machine (best done in safe mode), and you should have a pretty lean, clean machine.
If you wish, you can pretty much strip away everything that isn't native to Windows and even do without a number of Windows components, though I'd suggest you retain at least an active, real-time antivirus. A firewall is a pretty near a gotta-have, too, if the machine will be used on the 'net at all. If you're not going to be doing any email checking or messaging, you don't even need an email client or a messaging client.
You can also boost system responsivenss by riding herd on your startup items; a lotta stuff will wanna start with Windows, but really does nothing while not actually in use other than eat system resources. Email and messaging clients, media players, mastering utilities, imaging utilities, spreadsheet and/or document reader utilities, and other stuff of that nature don't need to be running in the background waiting to be called up; any can be accessed via Programs or through desktop or Quicklaunch shortcuts. All you really
need running with Windows is whatever app you're using at the moment plus Explorer, Systray, and your resident security/privacy software - though if your operating system features it, its a generally good idea to not disable System Restore.
Links to the mentioned software (all web-accessible and free or fully-functional free-to-try) may be found in
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