Run Activity Monitor; go to File » Save and save a text file of everything that is running; then copy/paste the contents into a reply here. We can then look over what's running.
N**S is the user name. Only one user on the computer. these are all of the processes.
---------------------------------
Active Memory: 1.60 GB
Free Memory: 734.3 MB
Wired Memory: 955.9 MB
Used Memory: 3.28 GB
Inactive Memory: 762.1 MB
Total VM: 136.83 GB
Number of processes: 70
PID Process Name User CPU Real Mem Virtual Mem
0 kernel_task root 25.3 303.9 MB 3.01 GB
1 launchd root 0.0 764 KB 2.34 GB
10 kextd root 0.0 9.8 MB 2.34 GB
11 DirectoryService root 0.0 4.3 MB 2.34 GB
12 notifyd root 0.0 484 KB 2.33 GB
13 diskarbitrationd root 0.0 1.2 MB 2.33 GB
14 configd root 0.0 2.4 MB 2.36 GB
15 syslogd root 0.0 540 KB 2.34 GB
16 blued root 0.0 2.1 MB 2.35 GB
19 mDNSResponder _mdnsrespo 0.1 2.3 MB 2.35 GB
20 distnoted daemon 0.0 1,004 KB 2.33 GB
24 securityd root 0.0 2.2 MB 2.35 GB
25 coreservicesd root 0.0 8.5 MB 2.39 GB
28 ntpd root 0.0 704 KB 2.32 GB
29 krb5kdc root 0.0 844 KB 2.33 GB
32 usbmuxd _usbmuxd 0.0 732 KB 2.35 GB
37 mds root 0.0 24.3 MB 2.54 GB
38 loginwindow n**s 0.0 7.0 MB 2.67 GB
39 KernelEventAgent root 0.0 512 KB 2.33 GB
41 hidd root 0.0 924 KB 2.33 GB
42 fseventsd root 0.0 1.6 MB 2.34 GB
44 dynamic_pager root 0.0 332 KB 2.32 GB
50 autofsd root 0.0 500 KB 2.33 GB
72 WindowServer _windowser 4.8 64.5 MB 2.76 GB
79 cvmsServ root 0.0 412 KB 2.33 GB
91 launchd n**s 0.0 756 KB 2.34 GB
95 Dock n**s 0.0 15.4 MB 2.69 GB
96 SystemUIServer n**s 0.0 11.7 MB 2.66 GB
97 Finder n**s 0.0 32.3 MB 2.81 GB
99 coreaudiod _coreaudio 0.0 2.4 MB 2.34 GB
101 pboard n**s 0.0 312 KB 2.32 GB
102 fontd n**s 0.0 6.0 MB 2.38 GB
114 UserEventAgent n**s 0.0 2.6 MB 2.35 GB
121 AirPort Base Station Agen n**s 0.0 2.1 MB 2.62 GB
195 AppleSpell.service n**s 0.0 4.7 MB 2.35 GB
3921 iTunes Helper n**s 0.0 1.1 MB 2.60 GB
4224 DashboardClient n**s 0.1 42.5 MB 3.75 GB
4225 DashboardClient n**s 0.0 3.6 MB 934.6 MB
4227 WebKitPluginAgent n**s 0.0 288 KB 2.34 GB
69109 Google Chrome n**s 0.6 199.7 MB 1.34 GB
69115 Google Chrome Worker n**s 0.0 50.8 MB 1.03 GB
69116 Google Chrome Worker n**s 0.0 21.8 MB 997.3 MB
69281 Google Chrome Helper n**s 0.0 25.2 MB 958.7 MB
69870 Shockwave Flash (Chrome P n**s 2.8 54.1 MB 1.00 GB
69871 mdworker n**s 0.0 18.1 MB 2.37 GB
69880 Activity Monitor n**s 14.9 32.9 MB 2.78 GB
69882 activitymonitord root 0.9 1.5 MB 2.33 GB
69903 Google Chrome Renderer n**s 0.1 80.5 MB 1.06 GB
69925 diskimages-helper n**s 0.0 12.7 MB 2.36 GB
69933 hdiejectd root 0.0 1.6 MB 2.33 GB
69936 mdworker _spotlight 0.0 9.8 MB 2.36 GB
70072 SystemStarter root 0.0 984 KB 2.33 GB
70723 fmpd root 1.2 3.1 MB 599.7 MB
70790 cron root 0.0 900 KB 2.32 GB
70863 VShieldScanManager root 1.5 3.3 MB 603.9 MB
70901 cma root 0.0 12.2 MB 628.8 MB
70908 VShieldUpdate root 0.0 50.3 MB 637.9 MB
70959 Menulet n**s 0.1 5.1 MB 892.3 MB
70962 McAfee Reporter n**s 0.0 5.1 MB 896.2 MB
70969 VShieldScanner root 0.0 109.6 MB 697.0 MB
70970 VShieldScanner root 0.0 109.5 MB 697.0 MB
70971 VShieldScanner root 0.0 100.7 MB 694.6 MB
71006 McAfee Security n**s 6.4 10.9 MB 958.9 MB
71055 VShieldService root 6.8 8.1 MB 613.4 MB
71062 Google Chrome Renderer n**s 0.1 92.9 MB 1.08 GB
71069 imklaunchagent n**s 0.0 1.9 MB 2.35 GB
71070 Keyboard Viewer n**s 0.6 34.2 MB 2.72 GB
71078 Google Chrome Renderer n**s 0.0 67.8 MB 1.07 GB
71104 VShieldScanner n**s 57.7 86.3 MB 681.0 MB
71167 Google Chrome Renderer n**s 0.4 107.6 MB 1.08 GB