The LCR combination from the speaker company is a good suggestion, as are the dayton subwoofers. If your dad does want to upgrade, and doesn't want to do it all at once, I would suggest getting just a center channel from the speaker company. When watching movies, all of your dialogue is going to come from the center channel, and you will notice a big increase in sound quality for the least amount of money. The speaker company sells a good center channel for $50 with free shipping. Later down the road, you could add new front left and right speakers and a subwoofer. You could try to recoup some of your money by selling the speakers on craigslist or ebay as you replace them.