As to the games: It's Fallout. By this point, one shouldn't need a review of the games. They're amongst the best games of all time (Tactics excluded), and no recommendation can be high enough. They just don't make 'em like this anymore.
However! Something has to be said about the reliability of the games. First: you likely will need to crack Fallout Tactics. For whatever reason, in Vista, the game does not recognize the CD as being a game CD. Thankfully, gamecopyworld.com is still a bountiful resource for safe No-CD cracks.
Also, from what I've heard of friends' experiences with this collection, some of the bugs that Fallout and Fallout 2 experience on WinXP are serious enough to ruin the game experience. For what it's worth, Vista has had no game-breaking issues with any of the collection so far.
There are, however, odd graphical glitches (the game screen has a tendency to suddenly go black; saving when this happens clears up the issue), and certain still-unresolved gameplay bugs that amount to minor annoyance.
Greater on the annoyance scale is that the games *still* bother you to register them despite both Interplay and Black Isle no longer existing, and the publisher of this collection, GSP, seems to have their own agenda trying to push a "register and get a free game" thing. Once again, individually small issues that add to the larger annoyance factor.
Bottom Line: It's Fallout. Play it. Sure, there are some annoying technical issues, but lets be realistic. It's Fallout.