Boat, the first step is to determine where you want to go with your system. Are you looking perform a modest upgrade, or do you want to completely transform your current setup? Once you make this determination you can then realistically come up with a budget.
Regarding home theater, I am of the opinion that the picture completely overshadows the sound. If I were putting together an HT system I first would focus on the video. For my taste a 27" monitor is too small and an upgrade to a 35/36" would reap big benefits. Also depending upon your viewing habits a center channel may not be required. A center channel is used to fix the sound at the monitor for off center-line viewers. If that's not a factor in your house, then skip the center channel and spend the money on better main (front) speakers.
Regarding home theater, I am of the opinion that the picture completely overshadows the sound. If I were putting together an HT system I first would focus on the video. For my taste a 27" monitor is too small and an upgrade to a 35/36" would reap big benefits. Also depending upon your viewing habits a center channel may not be required. A center channel is used to fix the sound at the monitor for off center-line viewers. If that's not a factor in your house, then skip the center channel and spend the money on better main (front) speakers.