Hello Gone_Fishing,

Quote: "I have downloaded the AVG rescue disk on a USB. I have tried running it on my HP mini, with no success. When trying to launch it freezes on "swithching to arl rool file system on /mnt/root........."

Please try use different Linux based live distribution(Ubuntu). For creating a bootable Live USB drive you can use UNetbootin.

Quote: "When starting in normal mode it freezes with a blank black screen after the "Windows" logo. I have tried booting in safe mode but freezes on "avgrkx86.sys and AVGIDSEH.sys"

For help on your situation please check my answer here.

Thank you