There are two ways to have Syslinux coexist with Windows 7 or Windows Vista. The traditional way, of course, is to mark the Syslinux partition active and use chain.c32 to boot Windows:
# Windows 7 on partition hd0,1 (hda1) LABEL win7 MENU LABEL ^Windows 7 COM32 chain.c32 APPEND hd0,1
Windows 7 is known not to hibernate properly if the Syslinux MBR is used; the standard Windows 7 MBR can, however, be used to run the Syslinux partition, at least in the stock retail install.
Some OEM installs have been reported not to be able to boot Syslinux from the stock Windows 7 MBR. For that case, or for those who prefer to minimize the impact on Linux, Syslinux can be booted from the Windows boot manager, BCD.
To do that, you need to install Syslinux normally, and then install NeoSmart EasyBCD. Create a new boot entry of type Linux/BSD > LILO/eLILO. Although Syslinux is not LILO, they work identically for the purpose of EasyBCD.