boot problems

Hello,

I have tried to modify my ssd drive partition type (from gpt to msdos) with gparted but I think I've messed it up! I guess I'm in over my head now and I would aprreciate any kind of help!

Furthermore my bios not always finds mx ocz Vertex 4 ssd drive. I have seen it several times listed but then it can be suddenly gone the next time I go into my bios. This also has been the case within Gparted...

I have tried to setup the SSD after erasing it (and changing the partition style to msdos, as gpt style originally prevented the installation of windows 7) but I think I haven't correctly managed the boot issue. I have flagged a small primary partition with boot but that's all. For the rest I have made 2 more primary partitions... and one ext partition. Now as I start a new windows installation from a boot cd, the first part of the installations seems to work but on the first time it reboots for the next step it hangs and says smt like failed to boot... I can thus only boot from the cd which then again starts the installation from scratch.. So I guess the sdd drive (I have the same issue now with the originally installed hdd-drive!) is not able to boot???

Can somebody please tell me what to do in gparted?? What setup should I have for both the drives, hdd und sdd (this should be the os drive) and how can i make them bootable....

Thanks a million!

Asus with i7 processor and 2 harddisk slots
OS: windows 7