Laptop lamentations

Alas! My laptop has started giving me problems!

1. There's now a very sluggish response to every command.
2. The appearance changes to Windows Classic soon after startup.
3. The sound comes out in slow-motion [no DirectSound driver?]
4. Long bootup time.
5. Super-long Windows disk check.

Have contacted Acer but no reply yet. Help!
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Believe it or not, after ten days, Acer has not replied my email.