Wireless not working properly on brand new Toshiba C55-A with Windows 8?

I literally just bought this computer within a few hours. I'm not a computer expert, but I'm not a total idiot.

I got the computer home and the wireless signal is terrible. It works, slowly, everywhere but the bedroom. In the bedroom, it doesn't really work at all. (that's the opposite side of the house from where my router is.) However, everywhere in the house, including the bedroom, my Sony laptop, iphones, xbox, Wii and pretty much everything else works great and are very fast on Wi-Fi.

First - I tried calling Comcast. They told me to shut off everything else and see if it works. It didn't help much at all. Still slow in the rest of the house, and it took about 10 minutes for anything to load in the bedroom, but then wouldn't go anywhere or do anything. They pretty much told me to call Toshiba, so…

I called them, and they wanted money to even speak to me and just pretty much refused to help whatsoever.

What could be the issue here? Is the wireless card just poor on this laptop? That seems a little strange, even the Comcast guy figured it should work. I asked about a signal booster and he said it would distort my connection, is this true?

What could I do to fix this and make my wireless connection work better/at all? Is a signal booster worth the money/will it mess up the connection?

Some info:
Toshiba Satellite C55-A
Windows 8
Realtek wireless card (that's all I know regarding that)

Please let me know if you need anymore info. Thanks

Added (1). I got it from Staples, I called them and they basically said it wasn't their problem but to call Comcast/Toshiba, but if I wanted to return or exchange it I could. But I want this model, and for a $500 I would assume the internet should work properly. Staples will "fix it" for a price for their tech support as well.

I even called Best Buy and they said for $100 they could take a look at it but no promises on a fix regarding the wireless (Especially since it wouldn't be in my home, it would be at their store)

It's not that it doesn't connect at all. It finds my wireless connection and does connect it's just unbelievably slow everywhere in the house, and doesn't work in the bedroom even though it's saying full connection/signal strength

Added (2). I was thinking a signal booster but was told by Comcast it would distort my connection, or something to that effect. Is this true?

Ok, so you bought it so recently, why don't you just take it back to the store and explain your situation. Bring the receipt with you. They should be obligated to either replace it or fix it for you.

It is just a poorly made wireless adapter on the laptop. You could try to put a signal booster on the Wi-Fi.

Sorry but this is a common problem with W8. Update your driver & reset it again.