Well since I got the GRUB back now, I tried to start up Ubuntu. When I did that I got a load of errors, and someone suggested to do a fsck.ext3 -fyv /dev/sda2. I'm doing that now and it looks like my HD was entirely corrupted =P. It has been running for a few hours now, and 8 of the 10 blocks are corrupted.

Windows still gets a Trap

Have you done the right thing there should be nothing in sda2 because it is an extended partition defining the border of sda5 and sda6. I base of course the latest information from your post #7 assuming you did not change things aparted from creating sda5 and sda6 at the beginning of the old sda5.

Your sda1 Windoze partition could suffer certain amount of abuse in formatting etc and could have been damaged but that is none of Ubuntu business. Ubuntu will do an integrity check on every partition it is obligated to mount as you can hold it for responsibilty to read back any file you care to select.

If Ubuntu is conducting a check on sda5 and sda6 then your install ins't clean. Remember I advocated a reboot after a fat32 partition has been deleted? (Item (3) Post #9 refers).

The other possibility is your disk is on its way out and the hard ware corruption is accelerating. A hard disk should be looked upon as a consumable as every manufacturer guarantees only a finit number of spinning hours.

When in doubt post here the output of the partition table by "sudo fdisk -l", say in a booted Ubuntu Live CD.

Well with some help and a rescue cd I was able to get my mbr back (yay!), and now everything is working fine =). Thank you very much for all the help!

So a happy ending ha.