I need help replacing my bike's tube I recently popped the tube in my front tire and need help replacing it. I don't really know very much about bikes or the assortment of numbers on tubes, tires, and wheels. Here is what I do know:

The tire that popped has 700x35/43C on it.

The spare that I got when I bought the bike has A2 25/32 x 622/635 on it. 

I was told that the spare is not the right size for my bike. I inflated it just a bit to see what it looked like in my tire and it does seem a bit small as it looks like it has a bit of room.  .

I just got a spare tube that has a schrader valve and learned that those cannot fit through the hole in my wheel. I'm not sure but I think this is the type of tube I need to get http://www.amazon.com/Avenir-Bicycle-Presta-25-35c-27-Inch/dp/B002K2DQ4S/ref=sr_1_10?s=cycling&amp;ie=UTF8&amp;qid=1337452869&amp;sr=1-10 700 x 35-45c or 700 x 25-35c as I was told I need 35 to be in the range of the second set of numbers. Is this correct? Can I get these with a presta valve in a store (like Target, Walmart, etc local large merchant) or should I just order and wait?

For additional info: My actual wheel says it is 622x17 6061H-T6. On the inside of the wheel groove it looks like it is stamped 900x16. It looks like the tire name and brand is Alexrims G6000. It is a hybrid bike.
Any bike store, and probably any Walmart/Target/etc, will have what you need.

700C (or 650c, 26", 29", etc) is how big around the tube/wheel is, while the x23,28 or x30-42, etc are the width range. You want to find one that, as you mentioned, includes the target size within the range and is a match on size and valve type.

Based on the "replacement" not fitting, I'm thinking your wheel is a 700c/29" and you are most likely looking for the right tube: 700x[range including 35] with a presta valve. That said, if you have a local bike shop, swing in there and the bike mechanic can make sure you are getting what you need. In most cases, the tube is going to cost the same (it's actually cheaper at the LBS I hang at as they buy tubes in bulk and sell them at close to cost) and you will be sure to get the right item.

Bonus: Ask the mechanic if he'd mind coaching you through changing out the tire. Someone who has changed a couple hundred tubes can usually give you pointers on how to roll the tire back on without tools, hot to prevent a pinch flat, and how to make the whole process quicker and easier.