I have no idea why Azeez Nadeem has responded with advice about setting resolution - or (worse!) suggesting you adjust the actual images (using brightness or contrast - in Windows Photo Gallery of all things, but ignore his post.
What may have happened is one of two things.
1 - I think this is somewhat unlikely - but it is remotely possible that the images always were very saturated and your old display - and your old printer - simply printed them in a flattened manner, and while that worked for you, it may be that you over corrected to compensate for the flatness and now, with this new computer, you are actually seeing what the images really look like - as I said, that is probably unlikely - if you print these on some other printer (or a JPEG or two on an SD card to WalMart or Costco for printing - well, you can see whats what...
- You new monitor has some very saturated hi gamma default system settings or is using some wide gamut color management profile, and it is displaying your normal images incorrectly, and they appear very contrastly and or saturated...
so, you need to adjust them...
http://www.ithinkdiff.com/new-color-calibration-settings-in-windows-7/
I think this should help - if it does not help, feel free to email me at *** Email address is removed for privacy ***