Biostar is fine if you're not overclocking.
I have a Biostar and its actually overclocking better than any Asus motherboard I've had in the past. ^-^
Biostar TA890FXE to be exact. It has very good overclocking capabilities.
The 32-bit OS is not going to be able to utilize all 4GB of RAM, I suggest you upgrade to a 64-bit. If you send me a PM I can assist you with getting the 64-bit version for free.
If you activated the OS already then you can't return it, since the activation is tied to the motherboard for anti-copy reasons, to help ensure that only one copy of Windows is used per PC.