My sims 2 double deluxe wont work?

I bought sims 2 double deluxe about 2 years ago and had it on my computer (played it all the time) but my computer got a virus and we took it in to get cleaned up but they had to delete all files on my computer and the sims 2 was deleted also and now it wont let me re-install the game what should i do i have the sims 2 fun with pets, best of Business, university life collection, seasons and mansion and garden but cant installl those with out the sims 2 double deluxe and i would hate to have to buy it again