MBR, UEFI, GUID questions

I have w8-32 bit, installed on a 1TB hdd with MBR partitioning.
There are 3 main partitions of 100 GB each, and then the last partition has which 7 logical partitions of 100 GB each, except last one having whatever was left.
PC is basically 6 years old, Intel Pentium Dual core E2180, 2 GHz
BIOS is American Megatrends 0404, 1/7/2008

Now, Three questions basically -

1. I found on net that even if a harddisk is GUID partitioned, w8 would need UEFI support to boot from it.
So Before going through doing GUID partitioning, how do I check whether my BIOS/ PC/ hardware can support UEFI support or not?

2. of course I understand that I can backup all data, delete all partition and reformat freshly all over again into GUID, but that would be too much efforts.

So the question is - how to convert MBR partition to GUID without loosing data, if possible?

3. As only 4 main partitions are permitted in MBR system, the fourth partition has to have several logical partitions, but if that fourth partition goes bad, we can't recover data from any of the logical partitions with it.

So the question is - Can my 1TB harddisk have a mix of MBR and GUID partitions at the same time?
If it is possible, then I can have 3 MBR partitions, and remaining 6 as GUID partitions, so that their data can be recovered.

TIA
Rawat

Your PC needs to support UEFI to support GPT partitions...
A disk can only support one MBR or the other GPT - not both.
Can't say for sure anybody has had any luck just converting MBR to GPT

MBR support 4 primary partitions
GPT supports 128 primary partitions