Its fine too be high.
Packets are very very small chucks of infomation your PC is sending and receiving.
The reason its needed is to keep your PC connected to the internet.
These packets will set up quickest routing points to websites, etc.
and the type of infomation that is sent is your IP address (computers name to the rest of the internet world), etc. not your bank details or porn collections etc.
And again this is so your speed over the internet is as best as it can be.
My best advice I can give you is get a decent firewall (and always have it switched on!) and know what you are allowing through. Zone Alarms is good for this (and its free). And get some anti-virus software. AVG springs to mind because its easy to use, keeps itself up to date and again its free.
Give us a shout if you need any more help or clarification.