***Problem Resolved***
Hm, i still didn't understand what exactly helped you to resolve.
- DEP exclusion required, but it should be added on installation automatically.
- ddraw can cause troubles, but it's required to help with palette troubles. It's window mode should be also stable.
- run as administrator helps sometimes, but should not be mandatory.
War2 should usually work quite stable on win7 with default configuration without any steps listed above.
Appreciate if you find what exactly helped you to resolve.