grappling with configing HTTPD

[paul]

I have an issue with httpd causing spikes in the load on my VPS. And I'm trying to see what's the best way to tackle fixing it, or optimizing what resources I give to apache.

Where can I start ? A snapshot of from top. The load averages seem okay, but that might be off as I'm on a VPS, and I read that you can't always trust that number.

top - 15:38:13 up 1:06, 0 users, load average: 0.16, 0.36, 0.33
Tasks: 128 total, 1 running, 127 sleeping, 0 stopped, 0 zombie
Cpu(s): 3.1%us, 2.0%sy, 0.4%ni, 94.1%id, 0.3%wa, 0.0%hi, 0.0%si, 0.1%st
Mem: 2097152k total, 1557184k used, 539968k free, 46668k buffers
Swap: 1048568k total, 0k used, 1048568k free, 646444k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
----
----
9055 apache 15 0 240m 21m 484 S 0.0 1.1 0:00.00 httpd
9056 apache 15 0 389m 54m 7652 S 0.0 2.6 0:07.35 httpd
9057 apache 15 0 393m 57m 7604 S 0.0 2.8 0:15.29 httpd
9058 apache 17 0 397m 62m 7816 S 0.0 3.0 0:12.49 httpd
9059 apache 15 0 404m 68m 7764 S 0.0 3.3 0:15.64 httpd
9060 apache 15 0 403m 68m 7880 S 0.0 3.3 0:15.30 httpd
9061 apache 18 0 402m 66m 7528 S 0.0 3.2 0:11.65 httpd
9062 apache 15 0 390m 55m 7556 S 0.0 2.7 0:07.01 httpd
9063 apache 15 0 402m 66m 7732 S 0.0 3.3 0:05.85 httpd
9129 apache 18 0 395m 59m 7776 S 0.0 2.9 0:08.13 httpd
9156 apache 15 0 394m 58m 7724 S 0.0 2.9 0:08.16 httpd
9193 apache 15 0 405m 65m 7912 S 0.0 3.2 0:06.96 httpd
9195 apache 15 0 392m 56m 7776 S 0.0 2.8 0:10.03 httpd
9196 apache 15 0 402m 66m 7732 S 0.0 3.3 0:05.05 httpd
10290 apache 15 0 392m 56m 7076 S 0.0 2.7 0:13.10 httpd
14370 apache 15 0 389m 52m 6180 S 0.0 2.5 0:02.66 httpd
14484 apache 18 0 393m 56m 6428 S 0.0 2.7 0:08.77 httpd
14486 apache 15 0 403m 66m 6992 S 0.0 3.3 0:03.74 httpd
14487 apache 15 0 393m 56m 6468 S 0.0 2.8 0:03.01 httpd

Are these values okay or insanely high?
Specs of the VPS are here, Blacknight Business+ VPS

My sites don't get crazy traffic, probably less than 10,000 uniques per day (i need to check). There are 60 domains hosted on the VPS. So far I've been happy with the VPS, since upgrading to PLESK 11 (sorry I don't have time to deal with a server without a panel) I've been getting these notices.