Having problem with gta3 pc file

well i downloaded a gta san andreas file from limewire and it opened the file and it reads as gta 3 with image of it showing. well the problem is that i used a winrar zip file to open and extract all files and download to computer. the file size is 251mb. when i downloaded the files it also had a read me. it said it had like 700mb file size with cd and the download i have was a rip of the cd. I try to open the gta3 file and i get a error message saying: "Unhandled Exception c0000005" Error Message and "Address at: 005ac3bb" i got every file it gave me from download. Can any one tell me what im missing or need to add or what the message means i need to do?

p.s. i think it has something to do with the backup. can anyone tell me how to do that?