MyPlayCity, Gametop, and FreeGamnePick do not have spyware, but all now have annoying toolbars and home page hijacking though technically it's not home page hijacking becasue you agree to it before you play the games via the checkboxes. Of those three I think Gametop are probably the safest as although whenever you install a game there is a page during the installation wizard that has two checkboxes that if not unchecked will see you with tool bars and a changed home page. If you uncheck these you should get the games for free without the tool bars and home page hijacking.
All do open your browser at the respective their sites when you close the game down but this is totally innocuous and serve to help you heck to see if any new games are available. If your home page is changed it's easy enough to change them back again. I posted a fix for doing this last week during one of the game giveaways as it's slightly different for each browser.
MyPlayCity used to be the best with no home page hijacking or toolbars but a few months ago changed their policy and now you are forced to accept both toolbars and the home page change, however you can change your home page back once your done installing all of your games and you can go into the tools section of your browser and turn off the toolbars. If you are confident enough you should even be able to remove all traces by deleting all of the registy entries and deleting the toolbar programs that you normally find in the programs folder, but also may be in hidden folders such as the Apps Data folder.
Personally I steer clear of them all now simply because there are many outlets that sell most of the latest arcade games dirt cheap. However I appreciate that not everyone can afford even those prices. If this is the case and your not happy with any site that installs those things (toolbars etc) then you could turn to the freeware games sites. We've posted details of thousands of free games many of which are just as good as the commercial games.
There were some misgivings about Jenkat games as well, but I haven't downloaded any games from them so can't qualify that. You can read something HERE about that. THIS one is all positive