Home theater in a box products are generally substandard! Save your money...I know $300 seems like a lot to you, but really, how much is that as a percentage of your income? Save your cash up, spend a bit more, and get a QUALITY system that you will enjoy for years! Your $300 purchase is almost guaranteed to end up in a landfill within the next 2 or 3 years...why not spend a little more and get something that will last?
If you are looking for a quality system on the cheap...take a look at the Martin Logan "Motion 2" satellite speakers for the front and rear speakers (Amazon has them at $199 ea) add the Motion 6 center channel for $299 and a Dynamo 500 subwoofer for $495. For the AVR, I would go with the Onkyo TXNR509 at $249. The whole system as described would be $1839 plus tax. That is a lot compared to the $300 you said you had to spend, but in the grand scheme of things, is very little. You could probably afford a system like this if you saved up for just a few months. In exchange, you will have a quality system with FAR superior sound, that will last you and your family for YEARS. Also, don't be afraid to purchase a few parts at a time if you cant afford the whole thing at once! Get 2 speakers and the sub, then add the center and rear speakers later! You will get FAR more enjoyment out of a 2.1 system using these speakers than you will with 5.1 channels coming out of the HTIB products you mentioned!
Remember, unlike flat panel displays...which keep getting less expensive as the technology matures...with speakers, you get what you pay for. Cheap speakers will have cheap components and cheap enclosures and will sound tinny and thin. Good speakers need quality materials, more copper for the voice coils, bigger magnets on the drivers, and better materials for the enclosure. In other words, the more money you spend on a speaker (up to a certain point, it starts to get a bit fuzzy at the very high end) the better constructed the speaker will be, and the better it will sound!
The very best advice I could give you is to advise you to go to a brick and mortar store, LISTEN to what you are considering purchasing and then make an informed purchasing decision! BUT...if you go to a store, DO NOT waste the saleman's time if you are just going to purchase online! If you benefit from the store's demos and the salesperson's advice, pay them back by purchasing your gear from them!
