HP 700-216 D Drive almost Full

[gorillaperf]

I just bought a HP 700-216 12g Ram quad core. The D Drive is a "Recovery" disc, It shows almost full and when I am on line playing Poker it spikes at 100% How do I adjust the partition on it I was in it once but forgot how I got there

 

[i7Baby]

With Disk Management eg http://www.howtogeek.com/howto/windows-vista/resize-a-partition-for-free-in-windows-vista/

 

[gorillaperf]

I was able to shrink the C drive but it will not let me shrink the D drive. How does shrinking the C drive affect the D driver.
On Windows 8 the D driver is an "image recover disc" what does that mean. I do edit a lot of pictures so I know that is what is effecting the computer slowing down. I did a recovery and it fixed it but I know I will have this problem again. Is there an easier way to solve this problem

Thank you for your assistance

 

[i7Baby]

Image recovery disk is where the System Restore images are stored.