What are my possibilities as far as connecting this to a home theater receiver and having full 5.1/7.1 surround sound?
I am only going to have my pc, cable, and perhaps an aux cable connected as inputs to my home theater receiver. What are your suggestions as far as purchasing the home right theater receiver for myself?
First, get familar with HDCP and find out if your stuff is HDCP compliant. Not sure about that MB or the GeForce 9400M video chipset (guessing it is). Find out if your HDTV is also and if you have a TOSLINK out (probably good to go there also). http://en.wikipedia.org/wiki/High-bandwidth_Digital_Con...
IMHO... The ideal setup is to do HDMI cables from all your HDCP compliant devices (computer, cable box, Blu-ray, xbox, PS3, etc...) into your HDTV. This will give you audio and video from all devices going to your HDTV with a simple switch of your HDTV input button. THEN you need to get your digital audio from your HDTV to your reciever. This is where TOSLINK comes in so be sure your new reciever has a TOSLINK input (most new will). Run the TOSLINK cable out of your HDTV and into your reciever. Set your reciever to the TOSLINK input and the only thing you really need to do is turn your components on, change the HDTV input, and change the volume on the reciever. http://en.wikipedia.org/wiki/Tos_link
There are several variations to this setup. Your new reciever may have multiple HDMI inputs and be able to do the audio and video switching as described above through your HDTV. Either way, this should get you started. The keys in talking to a sales rep are HDCP compliancy and TOSLINK to keep cabling and digital audio simple.