Technical help

note, this is a technical assistance inquiry: I would've posted this to the technical help board but since I am a new poster the system will not allow this.

I have ~5 BTC on an old laptop (Windows 7) and I tried moving the balance to another client. At first I tried moving about 0.1 BTC just to see what would happen. The client debitted the balance but it never "took" (that is, I never received the 0.1 BTC, and I know it is a good address). The client informed me I should update immediately so I updated to the latest version (v 0.8.0). The client would not load the wallet so I googled around and found a solution that said try to move all the files out of this directory EXCEPT for wallet.dat:

c:\Users\[Me]\AppData\Roaming\Bitcoin

I made a copy of this folder elsewhere and emptied all the files except for wallet.dat, and I am now downloading the blockchain. However, intermittently I get this error:

System error: CDB(): can't open database file wallet.dat, error -30974

Which causes the client to close. Right now I am simply re-opening bitcoin, where it will run for awhile (download a maybe a few hundred blocks or so) and then close again.

So the current issues are:
1) the 0.1 BTC I mentioned above is still showing as being debitted from the total inside the local bitcoin client though there is no freceipt at the receiving address, and this is confirmed by blockchain.info
2) I cannot create a new address to send coins (though I'd be scared to try this again now anyways)
3) the client will not load the blockchain without indicating the error above and closing

Any help would be appreciated. I really don't want to lose $230 worth of bitcoin right now.