There are two ways of doing this:
First: Insert the 95 boot disk and reload Windows.
Second:
If you can see your files from the DOS prompt, copy them to disk. Doing the following steps will erase anything that you have on your hard drive.
You may have to reformat your hard drive and repartition. Use the WIN 95 boot disk.
Start first by partitioning it. Run FDISK at the DOS prompt. Remove the partition and reboot the machine. Then run FDISK again and create the partition. Reboot the machine once more.
(If you have a copy of WIN 98 I suggest installing that over 95). Re-install Windows Operating system, all your system drivers, and software.
Note: Compressing a hard drive is not recommended on any operating system. It slows down the speed of the hard drive and decreases performance. You are more subjected to a crash with a compressed drive.
Hope this helps.