Your cpu usage looks normal and typical.
Be careful how you interpret task manager cpu utilizations.
Windows will spread the activity of a single thread over all available threads.
So, if you had a game that was single threaded and cpu bound, it would show up on a quad core processor as 25%
utilization across all 4 threads.
leading you to think your bottleneck was elsewhere.
On ram, windows will keep stuff resident in ram in anticipation of possible reuse.
Overloaded ram is diagnosed by high levels of hard page fault rates.