Vista - Error Stop: 0x0000008E

I am a beginner as far as computer lingo but I have Windows Vista that's
worked fine for some time but over the past couple of weeks I've been getting
error messages. The most recent is Stop: 0x0000008E (0x00000000, 0x86EE3B6C,
0x00000000). I've read some on the error and they talk about disk space
(which is fine), changing video adapters (no idea what that means), checking
hardware vindor for BIOS updates (what is this?), disabling BIOS memory
options-caching, shadowing (no clue?). I am concerned that it is related to
the virus software we've been using (AVG Free 8.0). After having a difficult
time uploading this most recent version, we finally got it to load (sometimes
this happens because we are on dial up). But it seems that these error
messages started after that. one of the previous messages was a
Kernel_Stack_Inpage_error (Stop: 0x00000077....). Any ideas?