Use correct tag names for compatability with fwd decls.
Some old code checks that _WINDEF_ is defined in windef.h.

diff --git a/include/commdlg.h b/include/commdlg.h
index 2edb1a9..ee7545d 100644
--- a/include/commdlg.h
+++ b/include/commdlg.h
@@ -245,7 +245,7 @@
 
 typedef UINT (CALLBACK *LPCFHOOKPROC)(HWND,UINT,WPARAM,LPARAM);
 
-typedef struct
+typedef struct tagCHOOSEFONTA
 {
 	UINT  	lStructSize;
 	HWND 		hwndOwner;
@@ -265,7 +265,7 @@
 	INT		nSizeMax;
 } CHOOSEFONTA, *LPCHOOSEFONTA;
 
-typedef struct
+typedef struct tagCHOOSEFONTW
 {
 	UINT  	lStructSize;
 	HWND 		hwndOwner;
diff --git a/include/winbase.h b/include/winbase.h
index 1dc02bc..fb96b34 100644
--- a/include/winbase.h
+++ b/include/winbase.h
@@ -673,7 +673,7 @@
 } SYSTEM_POWER_STATUS, *LPSYSTEM_POWER_STATUS;
 
 
-typedef struct tagSYSTEM_INFO
+typedef struct _SYSTEM_INFO
 {
     union {
 	DWORD	dwOemId; /* Obsolete field - do not use */
diff --git a/include/windef.h b/include/windef.h
index 34b169b..6552ff6 100644
--- a/include/windef.h
+++ b/include/windef.h
@@ -18,8 +18,8 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-#ifndef __WINE_WINDEF_H
-#define __WINE_WINDEF_H
+#ifndef _WINDEF_
+#define _WINDEF_
 
 #ifndef WINVER
 #define WINVER 0x0500
@@ -343,4 +343,4 @@
 }
 #endif
 
-#endif /* __WINE_WINDEF_H */
+#endif /* _WINDEF_ */
diff --git a/include/wingdi.h b/include/wingdi.h
index a84241d..d3d64bd 100644
--- a/include/wingdi.h
+++ b/include/wingdi.h
@@ -516,7 +516,7 @@
 #define DEVICE_FONTTYPE     0x0002
 #define TRUETYPE_FONTTYPE   0x0004
 
-typedef struct
+typedef struct tagLOGFONTA
 {
     LONG   lfHeight;
     LONG   lfWidth;
@@ -534,7 +534,7 @@
     CHAR   lfFaceName[LF_FACESIZE];
 } LOGFONTA, *PLOGFONTA, *LPLOGFONTA;
 
-typedef struct
+typedef struct tagLOGFONTW
 {
     LONG   lfHeight;
     LONG   lfWidth;
@@ -653,7 +653,7 @@
 #define OBJ_ENHMETAFILE     13
 #define OBJ_COLORSPACE      14
 
-typedef struct
+typedef struct tagXFORM
 {
     FLOAT  eM11;
     FLOAT  eM12;
@@ -773,7 +773,7 @@
 #ifndef _TEXTMETRIC_DEFINED
 #define _TEXTMETRIC_DEFINED
 
-typedef struct
+typedef struct tagTEXTMETRICA
 {
     LONG      tmHeight;
     LONG      tmAscent;
@@ -797,7 +797,7 @@
     BYTE      tmCharSet;
 } TEXTMETRICA, *LPTEXTMETRICA, *PTEXTMETRICA;
 
-typedef struct
+typedef struct tagTEXTMETRICW
 {
     LONG      tmHeight;
     LONG      tmAscent;
diff --git a/include/winuser.h b/include/winuser.h
index 34c24ed..7490c64 100644
--- a/include/winuser.h
+++ b/include/winuser.h
@@ -1834,7 +1834,7 @@
 #define CURSOR_SHOWING 0x00000001
 
 /* this is the 6 byte accel struct used in Win32 when presented to the user */
-typedef struct
+typedef struct tagACCEL
 {
     BYTE   fVirt;
     WORD   key;
diff --git a/include/wtypes.h b/include/wtypes.h
index f125d40..f721267 100644
--- a/include/wtypes.h
+++ b/include/wtypes.h
@@ -219,7 +219,7 @@
 #endif
 #ifndef _TEXTMETRIC_DEFINED
 #define _TEXTMETRIC_DEFINED
-typedef struct {
+typedef struct tagTEXTMETRICA {
     LONG tmHeight;
     LONG tmAscent;
     LONG tmDescent;
@@ -242,7 +242,7 @@
     BYTE tmCharSet;
 } TEXTMETRICA, *LPTEXTMETRICA, *PTEXTMETRICA;
 
-typedef struct {
+typedef struct tagTEXTMETRICW {
     LONG tmHeight;
     LONG tmAscent;
     LONG tmDescent;
diff --git a/include/wtypes.idl b/include/wtypes.idl
index f030245..4004434 100644
--- a/include/wtypes.idl
+++ b/include/wtypes.idl
@@ -220,7 +220,7 @@
 
 cpp_quote("#ifndef _TEXTMETRIC_DEFINED")
 cpp_quote("#define _TEXTMETRIC_DEFINED")
-typedef struct
+typedef struct tagTEXTMETRICA
 {
     LONG      tmHeight;
     LONG      tmAscent;
@@ -244,7 +244,7 @@
     BYTE      tmCharSet;
 } TEXTMETRICA, *LPTEXTMETRICA, *PTEXTMETRICA;
 
-typedef struct
+typedef struct tagTEXTMETRICW
 {
     LONG      tmHeight;
     LONG      tmAscent;