If you game, you may wish to install your games to the hard drive. I have a "STEAM" and "GAMES" drive both on my hard drive.
A 128GB can support a few games, depending on size. Be aware that:
1) A 128GB SSD probably has a usable space of about 118GB
2) My Windows 7 install was 35GB (8GB of System RAM) with Hibernation enabled shortly after installation.
3) My Windows 7 install ballooned to over 50GB within six months (updates, System Restore Points and programs)
4) I installed two games, a few more programs and my usage jumped to over 80GB after a year.