Problems with 3.0

I've started having problems yesterday.

1. When an app is trying to download, it will download half but does not complete until several minutes later (even with apps that are less than 1 MB).

2. ALL of my third party apps close immediately after I open them. Apple's apps are the only ones that open.

3. This may have already been discussed before, but text messages longer than two lines ends up getting stuck and will not let me scroll back to the top of the message input window.

I have more but this is all I could think of right now. Anyone else experiencing this too? I would really like to fix #2. Will I need to reinstall 3.0? restore? I have already restarted my phone several times to no avail.