60GB is basically unusable. Even if you try to keep it to "just the OS", it WILL fill up quickly.
The OS is much more than just the Windows folder.
A 60GB SSD is really only ~40GB actual usable space to you.
A 120GB is marginal, a 250GB is preferable. And at todays prices, it makes little sense to go below 250GB.
Typical US prices at Amazon:
60GB - $40
120GB - $60
275GB - $99 (Crucial MX300)
If the $60 difference between $40 and $100 is too much right now, don't bother with the SSD. Add it later.