Highlightfish will allow you to set coulour and Highlighting.
Coded to work with OllyDbg and ImmunityDebugger, one plugin for both debuggers.
It supports the schemes published here: http://www.ollydbg.de/schemes.htm
If you have a nice and comfortable scheme, send it to me and I will add it in the next release.
Template structure (scheme):
for more information see included sample (GrayAngelfish.scheme).
You are asked to restart the Debugger, so please save your work (Debuggee analysis) first.