NeedAdvice/replace.batt& Ram 4 Inspiron

Hi. I'm new here and need help. I bought my daughter a Dell Inspiron E1405. My first question: Do I have to buy her a batt. from Dell for $154 if they are even in stock or can I buy an after market battery from a place like comptick.com? They have the batt she needs there on sale today for $89 from $139. It says its a 9cell LI-Ion battery , 11.1v, brand new battery validated compatible with E-1405 and comes with one year warranty. The 7200mAh is regularly $139 and is on sale for $89. They also offer a 5200mAh $149 for $79. The batteries are manufactured by MayDay Technologies.
Does this sound like a battery I'm safe in purchasing for this computer?
2nd question-I'd like to upgrade her computer that currently has 1014MB memory (Intel Core Duo) to 2GB. Comptick offers 1GB DDR2-533 Laptop Memory for $61.78 on sale for $24.98. The memory comes with a Life time replacement or repair warranty or a 30day moneyback guarantee when returned in like new condition.
3rd question: If this is good memory do I need to buy two 1GB chips to upgrade her lptop to 2GB? THat makes sense to me because it has 2 -512 chips in it now.
Thank you in advance for any advice you folks can give me. I don't have a lot of spare money lying arond so that's why I"m trying to find the battery and memory at a discounted price instead of full price at dell.com. My DH had been laid off work for a long time and just got to work so money is tight. Thanks again for any replies and any advice you can giv eme is greatly appreciated!!! plantfreek in Bltgn, IN

 

ok what did I do wrong in my first message above here? The 2gb ram is on it's way from Dell-it's a one chip deal for just $34. I thot that was fair. My real concern is getting her a new battery. Is it ok to buy a new battery from somewhere else like comptick or do I have to get it from Dell? Please help me out here asap. Thanks a lot!

 

As long as it's a genuine Dell battery, it should be fine regardless of where you buy it (assuming it's new, or little-used). Some third-party or OEM batteries may be just as good, but often, they are pieces of junk. I would personally not buy anything but a genuine battery. If you have 2 x 512MB of memory, you will need 2 x 1024MB of memory to make the jump to 2GB. 533MHz DDR2 DIMMS will work fine.