So, I'm a noob and did a few silly things:
1) I had windows 7 installed
2) I installed ubuntu using wubi
3) I migrated my wubi installation onto a partition, but I used the Windows recovery partition (I'd done that once on an old computer and worked ok)
4) Ubuntu worked great, but I lost the ability to boot into Windows
5) Taking gregrocker's
advice, I used the partition wizard minitool to try to rebuild the windows mbr: the windows partition was already active, and then clicking on the HD, I selected "rebuild MBR"
6) I tried rebooting but got an error and no boot!
7) I tried making my ubuntu partition the active partition, (and also the swap partition) but still no go.
Now I can't boot into anything! Please help.