Software Installation Problems

Hi there,
I recently built myself a 7 prof desktop for general use.

I've been battling long and hard trying to convince Windows 7 to recognise many of my older bits of software and drivers.

Whilst this is a pain itself, worse is that I've now got 3 programs which started their instalation process -> rebooted the system -> came up with an error message at boot up effectively saying they can't complete the install.

The problem is that windows uninstaller (or the programs own uninstall) won't run to get rid of the programs and error messages which come up every time I boot.

Can anyone tell me how to manually get rid of these programs???

Thanks