1. Look up the serial number in this database: https://spreadsheets.google.com/ccc?...3c&hl=en#gid=0
2. If I recall correctly, another user on either this forum or another has stated that you can get an idea of the boot1 version in correlation with either the date code on the CPU or a letter in the CPU code. I'm not 100% sure on this as I have not verified it myself and it was a while ago I read this.
What you need to know is that only boot1a and boot1b are capable of having bootmii as boot2. So boot1c and above are not compatible. (no exceptions)
If you have either boot1a or boot1b, the only way you are ever going to recover that Wii is to flash bootmii into boot2 using a NAND flash programmer such at the Infectus chip. I'm sorry but there are no exceptions to this rule either. At least for the time being.
Hope this helps you sort out the problem. Good luck!