This is a relatively new model of printer. It is rare to find anything built in the last few years which isn't compatible with Windows 7, although any device can have problems with any system.
Windows 7 (32 bit) drivers can be found in the related links section.
Most popular models are compatible with win7.
Yes, as long as you download the windows 7 drivers for the photosmart from the hp website
The HP Photosmart series is compatible with Mac OS X. (See links below)