Of course. Yes, the SSD has a small capacity, but you don't really need a lot of space for your most common applications. I have Windows 7 Home Premium, Office 2007, and a couple of games installed on my 80GB HDD. While I do have very limited hard drive space on my C: Drive, it's been that way for years will no ill effects.
for some, the speed gains are totally worth it.
for others, the more touchy nature and crappy reliability of the low-end SSD that most people can afford to buy are NOT worth the hassle.
FYI - a 750G WD Black 2.5" costs less than a 120G SSD, is noticeably (but not ridiculously) slower, is much more reliable, has way more space, and a longer warranty. but it does run a little bit warmer (not much, but ya a bit), and doesn't like being shaken-n-stirred while in use.